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Lectron Carb Self Adjusting Carburetor – Review And First Ride

I Finally Bought A Lectron Carburetor For My KTM 300XC-W!

Lectron Carb Review And First Ride - Lectron Self Adjusting Carburetor - Featured

I finally bought a Lectron carb because since I bought my KTM in 2014, I have had to re-jet my stock Keihin PWK carburetor every single time I wanted to ride.

This bike is so finicky that it needs a different jetting for every 2,500 feet of elevation, and every 20 degrees Fahrenheit. And since I have to travel at least 3 hours in any direction to find trails, this was an inconvenience.

I also started having constant tuning problems with my carb about six months after I bought the bike, and I could never get it to run right above 90 degrees, regardless of elevation.

I Finally Installed A Lectron Carburetor On My 2014 KTM 300 XC-WI was so tired of fighting my carb, to the point that I didn’t even bother taking my KTM on riding trips. I considered selling my bike and buying a fuel-injected 4-stroke or TPI 2-stroke, but that was not a practical option.

So what is the best compromise? A carb that you don’t have to think about. And that is the Lectron Self Adjusting Carburetor!

First Impressions:

I was excited during unboxing, but that took a nosedive as soon as I started reading the setup guide.

The manual made it sound like all the Lectron carburetor does is remove the jets and replace them with the metering rod, and I had to remove the carb to adjust the rod to where I’m riding.

If I have to take it off every time to adjust to it than what’s the point? Why did I shell out $500 for a carb that still needed adjusting, I would have just got a dial-a-jet system and saved $400

I was wrong about that; I know that now. But I’ll get to that in a minute.

Lectron also provides a set of breakdown pictures for cleaning, which is nice, because I wanted to tear this thing down and see how it worked as soon as I got my hands on it.

Initial Likes & Dislikes:

Likes

Right away, I noticed they used Allen screws for the fuel bowl and slide. It doesn’t seem like much, but that attention to detail is appreciated considering every rider I know replaces the stock Phillips screws immediately.Allen Screws For Bowl And Slide Cover Speaking of the fuel bowl, it’s clear. I can monitor my fuel level, and see if any contaminants made their way into the bowl.Clear Fuel Bowl Lets Me Monitor Fuel Levels I also noticed that the carburetor body is made of two cast aluminum halves joined with Allen screws, meaning I can get to the internals during cleaning.Carb Is Constructed Of Two Cast Aluminum Halves However.

Dislikes

The clear bowl is one solid piece and has no drain; I have to pull the main jet hose and drain with a vacuum pump and catch can.No Drain On Bowl Have To Drain Bowl From Main Jet HoseI like the Allen screws for the bowl and throttle, but the hardware is standard. Almost all motorcycles are metric, so why would you assemble your carburetor with standard hardware?

I know it’s not a huge deal, it’s just, why?

The slide has no catch or lock to keep the throttle cable in place. Not having a cable catch doesn’t affect the operation or installation; I just found it odd because I’m not used to it.

Carb Size And Configuration

The Lectron carb is longer than stock, so It wrinkles the boot from the airbox. It’s not much, and If it does affect airflow negatively, the power gains compensate for it. The install guide says to cut the boot back if needed, but for my application, I don’t think that’s necessary.Carb Is Longer Than Stock And It Wrinkles The Air Box Boot The choke knob is on the wrong side of the body, so I have to reach between the hot exhaust and frame to disengage it.

My bike starts harder now. I can feel a big difference with my right leg. My initial thought is because the Lectron has no idle circuit, meaning the engine is fighting more vacuum at startup.

Whatever the cause is, I can not start my bike cold with the electric starter; I have to kick start it every time. I would be hesitant to buy a Lectron if I had a newer bike without a kickstarter. Which, by the way, not having a kickstarter is stupid, but that’s just my opinion.

If you or someone you know has a Lectron newer on one of those bikes with no kickstarter, let me know how that’s working out, I’m genuinely curious.

One More Dumb Thing

The fuel line does not come with clamps, and none of the promo pictures for the Lectron have clamps. Why would you want to risk popping a fuel line? Maybe Lectron just assumes you will reuse the stock clamps? I can’t imagine two tiny hose clamps would save them much overhead, but I’m not their CFO.Lectron Official Promo Image With No Clamps On The Fuel L‌ine Remember, this is just what I noticed fresh out of the box, and in no way affects performance.

Lectron Self Adjusting Carb Vs. OEM Keihin PWK 38mm Carb

I measured and compared everything I could think of on both carburetors to get some idea of why the Lectron creates more power with a smoother delivery.Measureing And Comparing Lectron To Keihin PWK AG6 I’ll spare you the wall of numbers, but what it boils down to is better fuel atomization, and I’ll get to that in a later video.

First Start-Up After Installation

Remember how I was wrong earlier? When Lectron says self-adjusting, they MEAN self-adjusting.

As I mentioned earlier, my old Keihin was a massive pain in the hot weather. The Lectron however, Did Not Give A F**k.

I installed the carb with the factory settings in 95-degree heat with 85% humidity. I felt like I was walking through a hot tub.

First kick, no throttle, and it started right up.  From pure muscle memory, I was on the kickstarter to try a second time before I realized my bike was running, and it stayed running.

You can imagine how excited I was to ride the next day on my new magic dirt bike.

Here is a cold start two weeks later on an even HOTTER day.

It was 95 degrees in the shade in my backyard, and you can see the jug is around 88 degrees, the choke is down, one kick start.95 Degrees In The Shade - Cylinder At 88 Degrees I haven’t needed the choke yet, but I’ll report back when I run this carb in 6 months when it’s 15 degrees outside.

First Ride With My New Lectron

The first ride with my new Lectron was in southwest Missouri over the 4th of July weekend, and guess what? It was hot and humid the whole time. But that did not affect my bike in the slightest.

I’m 340lbs, so I run the red spring on my 2-stroke because, well, I need all the power I can get.

With the Lectron carb, I felt a substantial increase in low-end grunt, I have never been able to tractor like this.

I’ve always started hill climbs in 2nd gear, then dropping down to 1st to stay in the powerband.

Now, I find myself upshifting on hill climbs. Which might not be legal in the United States?

Another first was cruising in 3rd and 4th gear, which felt weird because I don’t think I’ve ever touched 4th gear in the woods. Granted, that may be a skill issue and not a power issue.

But by far what I like most about my new found low down power, is having enough power to hold speed, but not so much I loop out if it gets away from me. Which, again, is a skill issue.

Final Thoughts On My New Lectron Carburetor

I am thrilled with my new carburetor because I can just go ride. I’ve never been able to do on this bike, and I’m looking forward to seeing how it performs when it’s nice out.

If you are having the same issue I had with my stock carburetor. Or if you want to forget you have a carburetor altogether, then I highly recommend getting a Lectron. It’s a much cheaper option than a new dirt bike, and bang for the buck, this has been the best aftermarket part I have installed by far.

If you have any questions about or experience with the Lectron Carburetor, let me know in the comments or on social.

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How A 2-Stroke Reed Valve Works

This Is How The Reed Valve Works In Your 2-Stroke Dirt Bike

How A 2-Stroke Reed Valve Works

The reed valve is easy to overlook during routine maintenance, and under-appreciated when it comes to performance.

In this article, I’m going to show you not only how it works, but also why it must function correctly.

To help demonstrate this, I built this air chamber out of plastic containers.  The 1st chamber is the carburetor, and the second chamber is the crankcase with the reed valve in between.  And for my engine, I’m using a vacuum.

Engine Analog Vacuum

Reed Valve Construction

Most reed valves are a simple design, and most are build the same way.  There will be a frame, petals, and in this case, a guard.  The pedals are made from various materials, depending on the age, make and model of the engine.Cage Over Petals Opening With Spacer Reed Valve Opening Reed Valve Petals

Steel, fiberglass, and carbon fiber are the most common.  The way the petals are secured varies, but if screws secure the petals, use thread lock!

Even the smallest of screws can wreak havoc on your crankcase!

Related: If you put a hole in your crankcase cover you moght be able to fix it with some JB Weld.

How A Reed Valve Operates

A reed valve is simply a one-way valve. The petals open during vacuum to allow the air-fuel mixture from the carburetor into the crankcase during the up-stroke of the piston. It will then close under pressure during the down-stroke to allow the mixture to be forced up into the cylinder.

Reeds Opening During Piston Upstroke

But it does much more than that.  The reeds also turbulate the incoming air-fuel mixture to atomize the fuel as much as possible before entering the combustion chamber.

Better fuel atomization means more efficient use of fuel, meaning more power.

What Happens When Your Valve Doesn’t Work Correctly?

When your reed valve is damaged or worn out, the air-fuel mixture can not stay in the crankcase when under pressure on the down-stroke.Reeds Close During Down Stroke This will result in less fuel entering the cylinder, causing power loss, and backflow into the carburetor, causing numerous problems.

(Learn how your 2-stroke carburetor works here)

Aftermarket Valve Assemblies

Many manufacturers offer reed valve upgrades.  The list is too long for this video, but if you want to go shopping, you can always find a great deal through Amazon!

If you have any questions or anything to add, please leave them in the comments or on our FaceBook page!

Keep Reading – How A Rim Lock Works

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How To Treat Exhaust Pipe Burn: Severity And Treatment – First Aid

How To Treat A Motorcycle Exhaust Burn With Basic First Aid

**Before you read any further, please use common sense, if your exhaust burn symptoms increase in severity, seek medical attention immediately! This article is for learning about burns and treatment before they happen!**

Exhaust Pipe Burns - First Aid: External First Aid TrainingRiding a machine powered by controlled explosions, your exhaust will get hot. When you go camping, you will most likely build a fire, which gets hot. When cooking over that fire, your pots and pans will get HOT!. Humanity has used fire to advance civilization over thousands of years, and fire can’t tell the difference between you and a hot dog. So always be mindful of where the hot is so you can avoid it.

No matter how careful you are, though, burns happen. This article will show you how to identify the degree and how to treat skin burns with basic first aid.

The first step in treating an exhaust burn is to determine its type: first, second, or third degree. The most effective way to determine the type of burn is to evaluate the extent of the damage caused by the trauma – or, to be even more specific, the layer of skin affected by the burn.  The more layers of skin damaged by the injury, the more serious the condition will be.

1st degree Burn
1st Degree Burn

First-Degree Exhaust Burn

First-degree burns damage the first layer of skin. One of the more common forms of a first-degree burn is the common sunburn.

Common symptoms associated with first-degree burns are a reddening of the affected area, mild swelling, and mild pain. The typical recovery time for a standard first-degree exhaust burn is 2-3 days.

Second Degree Exhasut Burn
Second Degree Burn (my leg after hot muffler contact) – click to view.

Second-Degree Muffler Burn

Second-degree burns damage both the first and second layers of skin. These burns are most commonly caused by exposed skin making contact with your motorcycle exhaust pipe, and by exposure to open flames or scalding liquid, like the coolant in your radiator.

Symptoms associated with second-degree burns are the same symptoms associated with first-degree burns, but with more severe pain and possible blisters. The typical recovery time for a standard second-degree exhaust burn is 2-3 weeks.

3rd Degree Exhasut Pipe Burn
3rd Degree Burns – Click to view

Third-Degree Exhaust Pipe Burns

Third-degree burns are the most dangerous type of burn and damage all layers of skin down to the muscle or bone.  These burns are also caused by direct contact with hot objects, flames, and scalds, with the difference being a more intense exposure than with second-degree burns.

Common symptoms associated with third-degree exhaust pipe burns include black, white, or yellow skin, massive amounts of swelling, leathery texture, and a lack of pain due to nerve and tissue damage.  Depending on the severity of the burn, recovery from third-degree burns can last anywhere from several weeks to several years.

Glowing Exhaust Pipe

Treating First & Second-Degree Burns

First and second-degree burns are, for the most part, managed using the same methods using basic first aid. There are certain occasions where second-degree burns will be treated differently.  Below, I’ve listed out the proper procedures under each circumstance.

First and (Mild) Second-Degree Exhaust Burn Treatment

  1. Flush the affected area with COOL water (NOT cold water).  Cold water (or ice) can lower the person’s body temperature and cause further damage to the affected area.
  2. Submerge the affected area in cool water for 10-15 minutes.
  3. Cover the area with a sterile gauze pad, or the Ace bandage from your trail pack.  Gauze keeps air off of the burn and helps reduce pain.  Make sure the pad fits loose over the area.  Adding too much pressure can potentially cause further damage to the skin.

 

Serious Second-Degree Muffler Burn First Aid

If a second-degree exhaust burn causes blisters and covers a significant area on the person’s skin, then further treatment is required beyond basic first aid to properly care for the burned area.

If Blisters Are Present

  1. Follow Steps 1-3 above. Make sure to keep the gauze pad loose (this will prevent blisters from popping).
  2. DO NOT POP any blisters that form on the surface of the burn.  These blisters have developed to help heal the affected area, and popping them could result in further complications and more pain.

If second-degree burns cover three inches or more of surface area:

  1. Follow the same steps found in Third-Degree Burn Treatment.

Third-Degree Exhaust Pipe Burn First Aid

You must get medical help immediately in all scenarios.  If you have a cell phone, contact 911 immediately.  If not, utilize the steps below, followed by immediate transportation to the nearest medical center.

  1. Do NOT remove any clothing, accessories, or other material from the burned area under any circumstances.  Doing so could cause further damage.
  2. Do NOT submerge the burn in cool water.  Cold water could potentially cause hypothermia or shock.
  3. Dress the affected area(s) with clean, cool, moist bandages.  Do not apply pressure on the bandages.  Let them rest lightly over the wound.
  4. Elevate the affected area, if possible, to further reduce swelling. (Rise above the level of the person’s heart.)
  5. If medical support cannot be acquired in 24 hours or longer, redress the burned area with clean, cool, moist bandages every other day.  Make sure to dampen the old dressing before removing it.

**Use common sense, if you think you need medical attention, get it! Improper treatment of burns can lead to lifelong scarring!**

If you have any questions or anything to add, please leave them in the comments or on our FaceBook page!

Back To First Aid Training

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Here Are The 8 Basic Principles To Build & Maintain Strength & Endurance

8 Strength & Endurance Principles for Enduro and Motocross

I think we can all agree that enduro, cross county and motocross is a brutally demanding sport and that your body plays a crucial role in how well you ride. That’s why it’s imperative that you make strength and endurance training a priority, second only to riding time. Because it’s through strength and endurance that you can maintain your balance, overcome arm pump, fight fatigue, and keep a rock-steady posture.

Rider Fitness: 8 Principles of Strength and EnduranceHowever, one obstacle that usually stands in the way of aspiring motocross and enduro pros getting started with weight training is a lack of knowledge of what they should be doing in the first place. There’s such a wide variety of information available on the internet about working out, but most of it doesn’t relate to dirt bike riders.

That’s why I’ve decided to list what I think are the eight most crucial strength and endurance training principles every motocross and enduro rider should follow to achieve significant results with their workouts.

I don’t claim that these principles are the be-all-end-all of training for riding dirt bikes, but they should serve as a solid foundation for achieving your goals. In other words, if you’re at a loss of where to start with weight training, this article will point you in the right direction.

Principle #1: Strength & Endurance Training Vs. Bodybuilding

Wickes hard enduro hill climb, looks fun!What’s essential to bodybuilders is how good they look in a V-neck. What’s vital to motocross and endure riders is how well they can maintain their balance and posture towards the end of a long race. Never forget that.

One of the leading reasons why some Moto riders claim that weight training is a bad idea is because they associate it with bodybuilding. Both consist of entirely different training methods.

Bodybuilding is not about getting stronger; it’s about sculpting the body to make it as visually appealing as possible.

Strength training is about getting stronger, period. And the stronger you become, the more control you can maintain over your bike.

Principle #2: Focus On Achieving Results Fast

Before anything else, you are a rider. This means you don’t have the time to spend two hours in a gym, six days a week. Focus on getting the workout completed as soon as possible, and then turn your attention to more pressing matters, such as putting in more riding time.

Principle #3: Focus On Total Body & Multi-Joint Workouts

Bodybuilders isolate. Motocross and enduro riders incorporate.

What I mean by that is that bodybuilders focus a lot on isolated exercises (dumbbell curls, triceps extensions, leg curls, etc.).

Enduro and motocross riders should focus on exercises that include multi-joint movements and workout multiple parts of the body. These workouts should also follow a natural range of motion (deadlifts, burpees, high barbell pulls, etc.)

First, ask yourself this question. Have you ever performed anything in everyday life that mimics the movement of a bicep curl?

Now, ask yourself this question. How often do you use the deadlift movement when you lift your dirt bike off the ground?

See? Natural movements are key.

Principle #4: Combine Circuit Training With Strength Training

Endurance is just as important as strength. However, running five miles in a day is time-consuming and not the best use of a dirt bike rider’s time.

Instead, work endurance training into your strength training routines by incorporating circuits into your routines. Circuit training is a high-intensity interval training system where you perform a complete circuit of exercises with no rest in between.

For example, let’s say your workout consisted of pushups, pull-ups, burpees, and side planks. So, instead of doing one exercise and rest, one exercise and rest, and so on, you instead do all four activities as quickly as possible with no rest in between exercises.

Once you complete all four exercises, that ends the first circuit. Take a quick 1-2 minute break and then perform the next circuit. Repeat until you have no less than four circuits completed.

Principle #5: Always Stretch Before & After Your Workout

Stretch like a cat and have the reflexes of a cat, math!

Stretching will provide a variety of benefits at different times during the workout:

Stretch before you exercise to loosen up your muscles and help prevent injuries during your workout.

Stretching the muscles you used in an exercise after you perform the activity is an excellent way to keep them loose while also increasing your range of motion.

After the workout, stretching helps decrease soreness and stiffness in your muscles.

Principle #6: Make Your Core A Focal Point of Your Workout

Posture is key to improving your riding. And if there’s one area of your body that helps most with maintaining your position, it’s your core muscles.

That’s right; your core isn’t just about getting six-pack abs. It’s about maintaining good posture and balance on your bike, and thus should be a significant focal point of your workout.

Some of the more proficient core exercises include ab wheel rollouts, bicycle kicks, planks, and medicine ball crunches.

Principle #7: Maintain The Proper Form With Each Exercise

Poor posture in the gym is the equivalent of trying to convince your wife to watch an American Chopper marathon with you. You can do it all you want, but you’re ultimately just wasting your time.

If you have poor posture with your exercises, then you’re not working the muscles as you should. You’re only giving a half performance. Not just that, but you’re sacrificing your safety as well. Most accidents in the gym happen as a result of poor form.

Principle #8: Make Time For Your Workouts

You’ve more than likely sacrificed this one before, I know I have. It’s tough to make time to workout, primarily when you’re not motivated to do it. But always keep in mind that the stronger you get and the more endurance you have, the better rider you will become.

You can always make the time. And don’t think it has to be 30-minute workouts every day. If you put in 10 minutes every other day into your rider fitness routine, you’re still doing something. And that’s the key, doing something. Use improving your strength and endurance as motivation and go out there and make it happen!

If you have any questions or anything to add, please leave them in the comments or on our FaceBook page!

Keep Reading – Stamina & Endurance

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2-Stroke Carb Tuning Guide For Your Dirt Bike

2-Stroke Carb Tuning And Adjustment

This 2-stroke carb tuning guide will give you all the information you need to tune your 2-stroke carburetor for peak performance, no matter the make or model. Once you understand the basic functionality of one 2-stroke carburetor, you can apply that understanding to ANY carburetor.

2-Stroke Carb Tuning - Air Fuel MixAlmost all 2-stroke carbs operate the same way. Although some may have different configurations or features, they all do the same thing – mix fuel and air.

Knowing how to change your jets and needles is one thing, but it won’t do you any good if you don’t understand how the changes will affect your dirt bike.

Parts of the Carburetor and What They Do

Carburetor Body

  • Body – The carburetor body houses all the moving parts and jets, and mixes the air and fuel on its way to the cylinder.
  • Bowl – The carburetor bowl is located on the bottom of the carb and holds the fuel to be sent through the jets. The bowl also houses the float assembly.
2-Stroke Carb Body And Bowl
2-Stroke Carb Body And Bowl

Internal Carburetor Components

  • Float Assembly – The float assembly sits inside the bowl to regulate the fuel level in the carburetor bowl. The floats are made of hollow plastic or metal connected to the carburetor body by a hinge. These floats need to be in good shape. No 2-stroke carb adjustments will work if the bowl is always flooding.

    Plastic Float assembly
    Plastic Float assembly
  • Float Valve – The float valve regulates the flow of fuel from the fuel tank to the carburetor bowl.

    2-Stroke Carburetor Float Valve Seat
    2-Stroke Carburetor Float Valve Seat

Air/Fuel Flow

  • Pilot Air Screw – Controls idle speed by regulating the amount of air passing through the pilot jet passage. This is where you will spend a lot of time during 2-stroke carb tuning. Getting that idle just right can be tricky sometimes.

    Pilot Air Screw
    Pilot Air Screw
  • Throttle Valve – The throttle valve is directly connected to the throttle cable and regulates the flow of air through the carburetor. You will almost always find a slide style throttle valve on 2-stroke carburetors. They come in many shapes, but their function is the same.

2-Stroke Carburetor Jetting Structure

Slow Jet

2-Stroke Carb Adjustment - Slow Jet
2-Stroke Carb Adjustment – Slow Jet

The slow jet works with the pilot air screw. This system controls the air-fuel ratio from closed throttle to ¼ throttle. The slow jet draws fuel from the bowl and mixes it with air from the pilot air jet passage. The atomized air/fuel mixture then passes into the throat of the carburetor. Turning the pilot air screw in will richen the air/fuel mixture while turning the screw out will lean out the mix. The slow jet is interchangeable with jets that will provide a leaner or richer air-fuel mixture. Replacing the existing slow jet with a higher-numbered jet will make the mixture richer, while a lower-numbered jet will make the mixture leaner.

Jet Needle

The jet needle is connected to the throttle valve and controls the mixture from approximately ¼ – ¾ throttle. The needle seats into the needle jet and regulates the air-fuel mixture from the jet to the carb throat. During your 2-stroke carb adjustment, pay close attention to the needle. The jet needle regulates fuel by its taper, diameter, and clip position. In the closed throttle position, the tapered needle shuts off flow from the needle jet. As the throttle is opened, the needle allows fuel to pass by the taper and between the straight portion of the needle and jet wall. The position of the needle in the jet can be adjusted by removing the needle clip and positioning it on a higher or lower groove in the needle. Raising the clip will lower the needle into the jet, creating a lean mixture; lowering the clip will raise the needle, creating a rich condition.

Main Jet

The main jet is screwed to the bottom of the needle jet and controls the mixture from approximately ¾ to full throttle. The main jet is numbered and is interchangeable with jets that will provide a leaner or richer air-fuel mixture. Replacing the existing jet with a higher numbered jet will make the mixture richer, while jets with a smaller number will make the mixture leaner.

2-Stroke Carburetor Main Jet
2-Stroke Carburetor Main Jet

Why Proper Carb Tuning Is Critical For 2-Stroke Engines

Improper 2-stroke carburetor tuning will have a much more significant effect on a 2-stroke engine than a 4-stroke because the premixed oil lubricates the crankshaft.  A rich mixture will cause poor performance, but a lean mixture can destroy your engine (over time).

At its most basic level, an engine is just an air pump, and what is mixed with the air is what makes it run. All a carburetor does is let fuel be sucked into the engine with the air.  This is where the sizing of the jets comes in.

Your carburetor needs to be adjusted according to the ambient temperature, humidity, and altitude of operation due to the oxygen density of the air changing with these variables.

If you have modified your 2-stroke with different reeds or an aftermarket exhaust pipe, you need to account for the increased airflow as well.

Carburetor Tuning Variables

Without getting into too much detail, below are some general guidelines on oxygen levels in the air.

  • Temperature – The colder the temperature, the denser the oxygen levels.
  • Humidity – More humid the air is, the less dense the oxygen levels.
  • Altitude – The higher you go, the thinner the air gets, resulting in lower oxygen levels.

If you want to get into the physics of air density, click here, otherwise, the above information will work.

Changing the carburetor jets is how you compensate for changing oxygen density: more oxygen requires more fuel to even out the air/fuel mixture.

Tuning Your 2-Stroke Carburetor For Peak Performance

There are three ways to tune your carburetor to the temperature and elevation.

  1. Factory Supplied Chart – If you’re lucky, your bike will have a jetting chart available from the manufacturer, so check with them first.
  2. Original Factory Configuration – If you know your carburetor’s factory settings, you will have a good starting point and can make more accurate adjustments.
  3. From Scratch – If you are starting from scratch, you will have to begin by making major adjustments and gradually narrow your tuning down. (Better in the long run.)

With each method, the only way to properly tune your carb is to keep track of every change you make and record the results.

Too Much (rich) Or Too Little (lean) Fuel?

The last piece of the 2-stroke carb tuning puzzle is knowing how to identify an unbalanced air/fuel ratio.

The simplest way to tune your carburetor air/fuel mixture is to look at your spark plug.

  • If the plug is black with soot, the mixture is too rich.
  • If the plug is white (burned), the mixture is too lean.

You can also determine the air/fuel ratio based on the performance of your dirt bike. If your bike bogs down under acceleration, the mixture is too rich. If you take off quickly, but your bike lacks power overall, the mix is too lean.

Fixing this is as simple as changing the main jet. Then you can go ride, but if you want to dial in the tuning of your carburetor from idle to full throttle, keep going!

Remember when the jets and needle come into play, and test the performance at each throttle position:

  • Slow Jet – Closed to ¼ throttle
  • Jet Needle- ¼ to ¾ throttle
  • Main Jet – ¾ to full throttle

Look for The Signs Of A Bad Ratio

  • Too much smoke = Rich
  • Too little smoke = Lean
  • Un-burnt fuel/oil sludge leaking from the muffler = Rich
  • Rough idle/no idle = Slow Jet System
  • Backfire = Lean
  • Bogging

Listen To The Bog

There are two types of bogging that will tell you if you are rich or lean.

  • Rich bogging sounds more of a “chug chug chug” sputter under throttle.
    • The “chug” is caused by too much fuel in the cylinder, resulting in incomplete combustion.
  • Lean bogging is a sustained “booooouuuuuuuuuhhhhhhhhg” under throttle.
    • The “bouhg” is caused by too much oxygen combusting, which does not create power on its own.
  • Typically, high-end bogging is lean, low-end bogging is rich, but the opposite is still possible.

You will need to start with a general diagnosis and narrow down what needs to be adjusted.

Follow the flowchart below to start tuning your carburetor! Remember to record every change you make along with the temperature and altitude. The following tuning flowchart is based on:

  • The ignition system is operating correctly
  • The fuel is fresh and mixed properly
  • The carburetor is clean, and the floats are adjusted
  • The air filter is clean

Side Note: If your carburetor is equipped with an idle adjustment knob, set it to a neutral position before adjusting the pilot air screw. (The idle knob is used for quick adjustments to the air-fuel mix and should not be used for tuning.)

2-stroke Carburetor tuning flow chart

**If you are experiencing poor performance, check the following before re-jetting the carburetor!!**

  • Bad fuel
  • Wrong fuel/oil ratio
  • Throttle cable dragging or out of adjustment
  • Air filter
  • Fuel flow – filter or fuel line plugged
  • Timing
  • Choke
  • Muffler
  • Brakes

If you have any questions or anything to add, please leave them in the comments or on our FaceBook page!

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Rider Protection: What Do You Have in Your Trail Pack?

What Do You Take With You In Your Trail Pack?

When I ride the trails, I always have my trail pack with me, and depending on where I am or who I’m with will determine what I have with me.  Extra weight is extra weight no matter what form it’s in, be it Gatorade, sandwiches or zip ties, every ounce has to be controlled by you, the rider.

What do you have in your trail pack headerAlways be prepared when riding, something as simple as electrical tape might mean the difference between riding or walking back to your truck.  You can’t take your toolbox with you, but you can take a few items that will do the job in a pinch.  This is a list of things I have in my trail pack.

What I Carry In My Trail Pack

  • Cell Phone
  • Whistle
  • Signal Smoke
  • Signal Flares
  • First Aid Kit
  • Ace Bandage
  • Master Link
  • Spare Tube
  • Air Pump
  • Electrical Tape
  • Zipties
  • Paracord
  • JB Weld
  • Hex Wrenches
  • Multitool
  • Socket Set
  • Multi-bit Screwdriver
  • Clif Bars
  • Gatorade
  • Camelback
  • Backup Gloves
  • Rubber Gloves

Let’s Start With Emergency Equipment

Every rider knows there is a certain level of risk involved with riding a dirt bike.  Flying through the trees on 250lbs of metal powered by explosions can get you hurt, so make sure someone can find you if you accidentally climb a tree or take a shortcut down a mountain. No matter how good of a rider you are, you will never be better than sh*t happens.  The following are emergency items I have in my trail pack EVERY time I ride.

Ride With A Cell Phone

No matter where I am riding I will always have, at a minimum, a fully charged cell phone in my trail pack.  I take a pre-paid flip phone I bought at Walmart for $15.  The phone is not activated, but if the phone has reception I can call 911.

I don’t like to take my smartphone on the trail with me because I like it and I don’t want to have to replace it.  If I am going on a long ride, I will wrap my nice phone in a small towel for some cushion, then put the wrapped phone in a zip lock bag to keep it dry.

Emergency Signals

Whistle: A $.99 white could save your life. You can’t yell as loud as you can blow a whistle, and you can blow a whistle a lot longer than you can yell.

Signal Smoke:  I carry a signal smoke stick that burns orange smoke for one minute, and is visible for 5 miles. Orange smoke is the universal help signal, and any law enforcement or EMS that sees the smoke will respond. And if local authorities don’t see the smoke, anyone with common sense who sees it will call it in.  Signal smoke isn’t cheap, (about $15) but it’s priceless when it saves your life.

Signal Smoke
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Signal Flares:  If you find yourself stranded at night, signal smoke won’t do any good, so I also have a four-pack of aerial flares in my trail pack.  These flares shoot up 450 feet into the air, burn for 7 seconds, and burn at 16,000 candelas.  If anyone is outside and one of these goes off, it’s tough to miss.

Side Note: Do NOT play with emergency flares or smoke, I set off an emergency smoke flare when I was a kid and the sheriff and EMS didn’t appreciate the false alarm.  If I were older, I would have received a considerable fine.

Signal Flares
Shop For Signal Flares On Amazon

First Aid On The Trails

First Aid Kit: I keep a basic first aid kit in my trail pack, mine is no bigger than a bar of soap, and I got it free from the American Red Cross.  My tiny first aid kit includes bandages, plastic tweezers, and alcohol swabs, but I mainly have it for the instant cold pack.  If I go down and sprain something, I can get cold on it immediately to avoid swelling.  However, a cold pack will not fix my dented exhaust.

I do keep a full kit at the camp/truck with all the big stuff like gauze, hydrogen peroxide, sutures, etc.

Another Side Note: Don’t try to stitch something if you don’t know how to do it, using tape will work until a medical professional can get to the injury.

First AidFirst Aid 2

Ace Bandage: An Ace Bandage can serve multiple purposes; compression for sprains, securing a cold pack, holding a splint in place, wet with cool water to treat exhaust pipe burns, etc.  An Ace Bandage is one of the most versatile tools in your trail pack, and they don’t cost much.

Ace Bandage
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Basic Supplies For Your Trail Pack

I would rather be hungry and thirsty than stranded, so tools take priority over food when preparing my trail pack, I can’t fix my dirt bike with a banana.  These tools will cover almost anything on the trail.  When I get a flat tire, I can still get back to the truck, when my handlebars are broken, I have bigger problems.

Master Link: If you manage to break a chain, a master link will get you back to the truck.

Spare Tube: You only need to pack the front tube. In a… pinch… You can shove a 21-inch tube in the rear tire.

Air Pump: A spare tube won’t do you much good without a way to fill it!

Spare Spark Plug: A fouled spark plug sill strand you just as easy as a flat tire.

Tape: electrical tape is the way to go, it can be used for easy waterproofing, and in an emergency can be used for compression or to secure a splint. Stay away from duct tape. Yes, in any other situation duct tape is the king of tape, but it’s useless when it gets wet.  Plus, 10 feet of duct tape is 10x bigger than 10 feet of electrical tape, so you’re using up a lot of space in your trail pack. (I may have exaggerated, but you know what I mean)

Electrical Tape
Any Hardware Store Will Have E-Tape

Zip Ties: It is loose? Zipties. What broke off? Zipties. Zip ties are essential for quick fixes, and they take up very little room. There’s almost no reason not to have them in your trail pack. Case in point, I have used zip ties to secure slipping dirt bike grips after taking my bike for a swim. I’ve even used them to secure the rear brake reservoir after a close call with a rock.

Zip Ties
Shop For Zipties On Amazon

Paracord: Parachute rope has an incredibly high tensile strength to size ratio. You can make a splint, tie your roost deflector back on, and even make a tow strap.

J.B. Weld: A cold EPOXY weld will fix or patch almost anything on your bike. Just make sure you bring the high temp epoxy so you can use it on the case and your brake lever perch.

Basic Tools For Your Trail Pack

Hex Wrenches: Considering there are no American-made dirt bikes, it’s safe to assume that every bike out there is metric.  I keep a multi-size Hex (Allen) wrench set with me.  I can do anything from adjusting the bars to removing the subframe.  What you want to avoid are packs of loose wrenches, they will get lost, it’s just a matter of time.  You also want to avoid cheap wrenches.  If your multi-wrench is made of plastic, you may have trouble if you need to loosen a stuck bolt.

I had a cheap multi-hex wrench shatter while adjusting my handlebars.  Sharp plastic vs. hand skin, plastic wins.  Fortunately, I was in my garage, so I was able to bandage the cut, but if that had happened on the trail, I would have been in trouble.  Plus, once the plastic frame breaks, you will have no leverage on the wrench, making it almost useless.

Multi Hex Wrench
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Think Compact

Multi-tool: Another important tool that needs to be of good quality.  A cheap leatherman knock-off won’t do you any good in your trail pack.  The quality of the construction and the quality of the steel in the tools could mean all the difference in a survival situation.  Cheap metal won’t last long under excessive use, like building a shelter. You can friend a decent price on Leatherman multi-tools on Amazon.

Socket Tool Thing: My first KTM came with a multi-use “T” handle wrench.  It came with sockets and screwdriver attachments.  KTM claims I can completely tear down and rebuild my bike with this thing, but I haven’t tried.  Fortunately, it’s very light and compact, and extremely handy.

KTM tool
KTM “T” Handle Thing

Screwdriver:  Obviously taking a bunch of screwdrivers with you would be impractical, but sometimes multi-tools aren’t good enough.  I picked up a 6-in-1 screwdriver from Home Depot for $2.99 and it’s working out great. The screwdriver has two different sizes of Phillips and slot bits and the bit holder doubles as a nut driver.

6 in 1 screwdriver dissasembled
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6 in 1 screwdriver

Food and Drink For Riding

Clif Bars: I prefer Clif bars for their natural (as natural as packaged food can be) energy and protein.  Power Bars are basically candy bars.  Those big Met RX bars are too bulky and expensive to carry on a dirt bike.  I can get a huge variety pack of Clif bars for around $30.  Clif bars also pack a lot of protein and calories in a small bar. You won’t get stomach cramps from eating too much and you won’t fill up your trail pack.

Cliff bars
Shop For Clif Bars On Amazon

Gatorade: Gatorade, not just “sports drink” is better than water, and WAY better than energy drinks.  Water does not replace minerals and electrolytes lost during exercise, and energy drinks dehydrate you.  Gatorade also gives you some calories to work with.  If you are serious about your hydration and performance, you should look into some intra-workout powders.

Camelbak (Hydration Pack): Camelbaks are an easy way to keep hydrated on the trail. They don’t cost much, and after a while, you will unconsciously drink a steady stream of water (or Gatorade) as you ride.  This eliminates the need to stop and the need to carry a bottle with you.  Most trail backpacks will have a Camelbak pocket if you want to keep things simple.

hydration pack
Shop For Hydration Packs On Amazon

Extras For LONG Rides

Backup Gloves: I keep a pair of backup gloves in my trail pack for long rides.  If I start to feel blisters forming, I can switch gloves to change the contact points on my hands.  Also, if I try to go swimming with my bike, I have an extra set of dry gloves.

dirt bike gloves
Shop Dirt Bike Gloves On Amazon

Rubber Gloves: I mainly keep rubber gloves in my trail pack for wet riding.  I can put a layer of rubber gloves under my regular riding gloves to avoid long-term exposure to water.  When your hands get wet while riding the chance of reduced feeling will increase exponentially (if it’s under 70 degrees).  The chance of developing blisters and sores increases as well.  Rubber gloves can also be used with electrical tape to seal things.  Plus, if your buddy goes down, you can wear your rubber gloves while administering first aid.

rubber glovesIt might seem like a lot of stuff for riding dirt bikes.  But, I can fit it all in a belt pack I used for hunting (It’s just a giant fanny pack).

everything for the trail packeverything for the trail pack in ziploc bagsWill Everything FitYes It Will

Also, I would rather carry some extra weight if it means I won’t get lost or stranded. I won’t get hungry or dehydrated, and most importantly, if I get hurt, I can patch myself up.  And in the worst-case scenario, I can call for help.  I hope this article will give you a good foundation for building your trail pack!

If you have any questions or anything to add, please leave them in the comments or on our FaceBook page!

Keep Reading – Maxima Racing Fork Oil Review

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1997-2001 Honda CR250 Master Repair Index

Master Repair List For Your 97-01 Honda CR250

Video: 1994 – 2001 Yamaha YZ125 – Carburetor Rebuild

How To Service The Carburetor on Your 1994 – 2001 Yamaha YZ125

 

The Tools You Will Need

  • Philips Head Screwdriver
  • 6mm Socket (Main Jet & Needle)
  • 14mm Wrench (Choke Knob)
  • 17mm Wrench or Socket (Bowl Drain)
  • Needle-Nose Pliers
  • Shop Towels

The Parts You Will Need

  • Jet Block Gasket
  • Needle Seat O-ring
  • Bowl Gasket (Maybe)

See the full carburetor service walkthrough here.

If you need parts and tools you can get them here!

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1994 – 2001 Yamaha YZ125 – Carburetor Rebuild

How To Service The Carburetor on Your 1994 – 2001 Yamaha YZ125

1994 - 2001 Yamaha YZ125 - Carburetor Rebuild - Featured

The Tools You Will Need

  • Philips Head Screwdriver
  • 6mm Socket (Main Jet & Needle)
  • 14mm Wrench (Choke Knob)
  • 17mm Wrench or Socket (Bowl Drain)
  • Needle-Nose Pliers
  • Shop Towels (Amazon)

The Parts You Will Need

  • Jet Block Gasket
  • Needle Seat O-ring
  • Bowl Gasket (Maybe)

If you need parts and tools, you can get everything you need on Amazon.com!

This carburetor is a Mikuni TMX38 found on the 2001 Yamaha YZ125. The 1995 – 2000 YZ125 came with a TMX36. They are very similar, so this service will cover both models. The 1994 Yamaha YZ125 came with a Mikuni TMX35, which is significantly different from the TMX36, so this service will not apply to that model directly, but it will be close enough.

The TMX line of carburetors has two weak points; the jet block gasket and the float valve O-ring. If you are having rich condition issues tuning your 2-stroke carburetor, these are usually the problem.

So before you even take your carb off your bike, I recommend you order the JD Jetting JDMK05 – Mikuni TMX Jet Block Gasket Kit. It comes with the gasket, 2 O-rings, and the Torx bit needed to remove the jet block.

Before you start, here are the carburetor components and where to find them.

Mikuni TMX Carburetor - Shock Knob And Throttle Stop Screw Locations-50
Mikuni TMX Carburetor – Shock Knob And Throttle Stop Screw Locations
Mikuni TMX Carburetor - Main Jet Slow Jet Floats Float Tab Float Pin Float Needle And Seat Locations-50
Mikuni TMX Carburetor – Main Jet Slow Jet Floats Float Tab Float Pin Float Needle And Seat Locations
Mikuni TMX Carburetor - Idle Circuits and Idle Jet Filter Screen Locations-50
Mikuni TMX Carburetor – Idle Circuits and Idle Jet Filter Screen Locations

Carburetor Removal

  • Remove the Fuel line, Loosen the boot and airbox clamps, and pull your carburetor out of your bike.
  • Remove the throttle slide cap screws, and pull the slide from the carburetor body.
  • Place your carb in a tray or on a towel to catch any remaining fuel.
  • Work the slide spring up the cable with a pair of needle-nose pliers until you have a good grip on the throttle cable.
  • Push the cable in and over to release it from the slide.
1 - Remove The Slide Cap Screws
1 – Remove The Slide Cap Screws
2 - Remove The Slide Spring With Needle Nose Pliers
2 – Remove The Slide Spring With Needle Nose Pliers

Carb Disassembly

  • Remove the bowl screws, and separate the bowl from the body. You want to be careful in case the bowl gasket is stuck.
  • Remove the jet shroud.
  • Remove the main jet, followed by the main jet mount.
  • Remove the slow jet carefully.
    • Do not attempt to force the slow jet out. The jet is brass and will break easily. If it is stuck, let it soak in penetrating oil, then try again.
  • Remove the float retaining screw.
  • Remove the pivot pin, followed by the floats and float needle as an assembly.
  • Remove the float needle seat retaining screw.
    • There is no gentle way to remove the needle seat.
  • Pry the seat out of the body with a small flathead screwdriver using the two slots on each side of the seat.
    • You may need to use pliers.
  • Remove the choke knob, throttle stop screw, pilot filter screen, and pilot air screw and spring.
  • Remove the jet block screws with the supplied Torx bit from JD’s.
  • Remove the jet block through the slide opening.
  • And if you haven’t done it already, remove the bowl drain.
3 - Remove The Float Needle Seat
3 – Remove The Float Needle Seat
4 - Remove The Jet Block Using JD Torx Bit
4 – Remove The Jet Block Using JD Torx Bit
5 - Remove The Jet Block Through Slide
5 – Remove The Jet Block Through Slide

Clean & Inspect

  • Clean the bowl and drain plug with carb cleaner.
    • My gasket wasn’t moving easily, and it was in good shape, so I left it in.
  • Remove the needle from the slide with a 6mm socket.
  • Inspect the needle for damage. If it is bent or anything other than smooth, it needs to be replaced.
  • Clean and inspect the slide. It should be smooth and shiny.  My slide had some corrosion on the bottom corners.
    • I should have just sanded the corners smooth with 300 grit sandpaper, but I didn’t, and you’ll see what NOT to do with a chromed part coming up.
  • Inspect the return spring for kinks; if it’s anything but spring shaped, it needs to be replaced.
  • Clean and inspect the choke knob. Check the o-ring, and check the action. The knob should click firmly into place in both directions.
  • Inspect the main and slow jets.
  • The slow jet is not a straight-through design. Spray carb cleaner through the end, and you should see it coming out of multiple openings.
  • You should be able to see straight through the main jet.
  • Clean all other components with carb cleaner.
  • Test your floats by submerging them in water.
    • If you see bubbles, you need new floats.
  • If you have the time, the most effective cleaning method is to leave your carb to soak in pine sol for about 12 hours.
    • If not, carb cleaner will work just fine; just make sure you reach the choke and idle circuits.
  • Thoroughly rinse your carb in water, then use compressed air to blow out the idle and choke circuits.
  • With the body dry, shoot WD40 into the circuits to void any residual moisture.
6 - Check The Jets For Obstructions
6 – Check The Jets For Obstructions
7 - Test The Floats In Water
7 – Test The Floats In Water
8 - Soak Your Carburetor In Pine-Sol Overnight
8 – Soak Your Carburetor In Pine-Sol Overnight
9 - Rinse Your Carburetor In CLEAN Water
9 – Rinse Your Carburetor In CLEAN Water
10 - Void Any Remaining Water From The Idle Circuits With WD40
10 – Void Any Remaining Water From The Idle Circuits With WD40

Don’t Soak Chrome In Pine-Sol!

  • So apparently, pine-sol dissolves chrome! I’ve never soaked a slide, so I thought I would see what happens. This… this happens, so… Lesson learned, and learn from me.
Don't Soak Chrome In Pine-Sol!!!
Don’t Soak Chrome In Pine-Sol!!!

Carburetor Assembly

  • Start your carb assembly with the new jet block gasket.
    • The gasket can be tricky to install, but some 2-stroke oil will help keep it in place.
  • Apply 2-stroke oil to the new float valve O-ring.
  • Install the new O-ring onto the float valve, and press the valve into the body.
  • Install and tighten the float valve retaining screw.
  • Install the float pin into the float, and float valve onto the tab.
  • Place the float assembly in the bowl, and secure it with the retaining screw.
  • Install the main jet housing finger tight, then use your socket wrench to get it snug, not tight.
  • Install the main jet the same way.
  • Install the slow jet.
    • Again, these jets are brass and can break easily.
  • Install the jet shroud.
  • Install the gasket and fuel bowl.
  • Install the choke knob with a new O-ring.
    • I am using the spare O-ring from the JD jetting kit on the choke knob.
  • Install the pilot air screw and spring.
    • The pilot air screw has a factory setting of 1 and ¾ turns out from seated for 1995 – 2001, and 1 and 5/8 for 1994.
  • Install the pilot filter screen
  • Install the throttle stop screw.
    • Turn in the throttle stop screw until you can see the tip in the body. Set it here, so the throttle closes completely and doesn’t interfere with tuning later.
11 - Install The New Jet Block Gasket With 2-Stroke Oil
11 – Install The New Jet Block Gasket With 2-Stroke Oil
12 - Install The Jet Block Gasket
12 – Install The Jet Block Gasket
13 - Install The Float Needle Seat With The New O-Ring
13 – Install The Float Needle Seat With The New O-Ring
14 - Install The Needle Seat Retaining Screw
14 – Install The Needle Seat Retaining Screw
15 - Install The Float Needle On The Float Tab
15 – Install The Float Needle On The Float Tab
16 - Adjust The Float Tab As Needed
16 – Adjust The Float Tab As Needed
Mikuni Pilot Air Screw Stock Settings
Mikuni Pilot Air Screw Stock Settings

Float Level

Float levels are all over the place between model years, if they even have them.

  • To check your float level, angle your carburetor, so the float touches the valve but not engaging the spring.
  • Measure from the top of the main jet to the top of the float arm.

Almost every year had a different float level, so make sure to check your model year carb specs here.

This carb has no float level specified, but it does have a fuel level specification. Of course, I need a special tool to measure the fuel level, and I’m not going to buy it.

A good rule of thumb is to set the floats parallel to the carburetor body.

Even if I have no measurements to go off of, I can tell these floats are WAY out of adjustment because the tab is bent way up, and the valve closes long before the floats reach parallel.

So I’m going to set my floats at parallel and keep this in mind while tuning the carb. If I find myself with an extremely lean or rich condition, I can start here.

  • If your float is out of adjustment, you can bring it back into adjustment using the float tab.
    • Bend the tab up to lower the floats and down to raise the floats in relation to the body.
Mikuni TMX Carburetor - These Floats Are Out Of Adjustment
Mikuni TMX Carburetor – These Floats Are Out Of Adjustment

Carburetor Installation

My bike is completely stripped, so Imagine the throttle cable is still attached to the bike.

Even though my slide is de-chromed, it’s still in one piece. I can use it, but I will be replacing it sooner than later.

  • Place the throttle return spring on the throttle cable, then grip the cable with needle-nose pliers.
  • Work the spring up the throttle cable, then install the cable into the slide.
  • Install the slide, then secure the slide cap with new hardware.
17 - Install The Throttle Cable In The Slide
17 – Install The Throttle Cable In The Slide

If you have any questions, please let me know in the comments or on social.

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Video: Oregon Sure Sharp Handheld Chain Sharpener

How To Setup And Use The Oregon 575214 Sure Sharp 12V Handheld Chainsaw Chain Sharpener/Grinder

See the full step-by-step guide HERE.

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Oregon Sure Sharp Handheld Chain Sharpener

How To Setup And Use The Oregon 575214 Sure Sharp 12V Handheld Chainsaw Chain Sharpener/Grinder

Oregon 575214 Sure Sharp 12V Handheld Chainsaw Chain Sharpener Grinder - ThumbHow To Setup Your Oregon Sure Sharp

  • The Oregon Sure Sharp kit includes three sharpening stones.
  • You want to use the largest stone that fits at the correct angle, which is parallel with the top of the tooth.
  • My chain can fit the smallest stone, but it does not contact the entire tooth, so I will be using the middle stone for my chain.
  • You want the stone to contact the entire tooth to avoid creating a shelf underneath the cutting edge.
  • Remove the guide plate to install the grinding stone.
  • Press the detent to stop the collet from turning, and tighten the collet.
  • Reinstall the guide plate.
  • To set the stone’s depth, loosen the guide plate adjustment screw, and fit the grinding stone in the chain tooth.
  • Set your depth, and tighten the guide plate adjustment screw.
1 - Three Grinding Stones Included With Kit
The Oregon Sure Sharp kit includes three sharpening stones.
2 - Use Correct Size Stone
You want to use the largest stone that fits at the correct angle, which is parallel with the top of the tooth.
3 - Too Small Of Stone Will Leave A Shelf Under The Blade
You want the stone to contact the entire tooth to avoid creating a shelf underneath the cutting edge.
4 - Install The Grinding Stone
Remove the guide plate to install the grinding stone.
5 - Tighten Collet
Press the detent to stop the collet from turning, and tighten the collet.
6 - Install Guide Plate
Reinstall the guide plate.
7 - Loosen Guide Plate Adjustment Screw
To set the stone’s depth, loosen the guide plate adjustment screw, and fit the grinding stone in the chain tooth.
8 - Set Guide Plate Depth
Set your depth, and tighten the guide plate adjustment screw.

How To Use Your Oregon Sure Sharp

  • Slightly twist the grinder toward the front of the bar to keep light pressure on the guard.
  • Work the grinding stone back and forth across the tooth to avoid uneven wear on the stone.
    • Stay within the width of the guard end to avoid hangups on the chain.
  • Depending on your chain’s life, you will need to file down the depth gauges to just below the cutting edge.
  • This can be done with a hand file or Dremel with a wide stone, do not use the supplied grinding stones. 
9 - Apply Slight Pressure To Chain
Slightly twist the grinder toward the front of the bar to keep light pressure on the guard.
10 - Work Stone Back And Forth
Work the grinding stone back and forth across the tooth to avoid uneven wear on the stone.
11 - Grind Down Depth Guage
Depending on your chain’s life, you will need to file down the depth gauges to just below the cutting edge.
12 - Use A File
This can be done with a hand file or Dremel with a wide stone.
13 - Use A Dremmel With Wide Stone
Do not use the supplied grinding stones.

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Video: 1994 – 2001 Yamaha YZ125 – Clutch Rebuild

How To Service The Clutch On Your 94-01 Yamaha YZ125

1994 - 2001 Yamaha YZ125 - Clutch Rebuild - FeaturedYou can remove and install your clutch through the clutch cover, but since I’m doing a full engine overhaul, my right crankcase cover was off during install.

Before you start:

  • Outline the clutch cover bolt pattern on a piece of cardboard and transfer your bolts from your engine to the cardboard as you go.
  • Everything will be covered in oil, so have baggies and towels ready.
  • Drain your oil.
  • Put your bike in first gear.
  • Disconnect your clutch cable.
  • You will need a clutch holding tool to loosen and torque the center nut safely.

See The Step-by-Step Clutch Rebuild Walkthrough Here

Clutch Specifications:

  • Spring Free Length – 38.1mm
  • Friction Disc – 2.7mm
  • Clutch disc – 1.2mm
  • Center Bolts – 59 ft-lbs
  • Spring Bolts – 88 in-lbs

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1994 – 2001 Yamaha YZ125 – Clutch Rebuild

How To Service The Clutch On Your 94-01 Yamaha YZ125

1994 - 2001 Yamaha YZ125 - Clutch Rebuild - FeaturedYou can remove and install your clutch through the clutch cover, but since I’m doing a full engine overhaul, my right crankcase cover was off during install.

Before you start:

  • Outline the clutch cover bolt pattern on a piece of cardboard and transfer your bolts from your engine to the cardboard as you go.
  • Everything will be covered in oil, so have baggies and towels ready.
  • Drain your oil.
  • Put your bike in first gear.
  • Disconnect your clutch cable.
  • You will need a clutch holding tool to loosen and torque the center nut safely.

If you need parts and tools you can get them here!

Clutch Removal

Clutch Pack

  • Loosen the clutch spring bolts in a criss-cross pattern.
  • Remove the pressure plate bolts and springs, and place them in a baggie.
    • The push piece is not secured in the pressure plate, so remove the pressure plate by the push-piece to avoid dropping the push piece assembly.
  • Wrap the pressure plate assembly in a shop towel to keep everything together.
  • Pull the plates and discs from the clutch, and wrap the clutch pack in a shop towel.
1 - Loosen Clutch Spring Bolts
Loosen the clutch spring bolts in a criss-cross pattern.
2 - Remove Pressure Plate
The push piece is not secured in the pressure plate, so remove the pressure plate by the push-piece to avoid dropping the push piece assembly.
3 - Remove Clutch Pack
Pull the plates and discs from the clutch, and wrap the clutch pack in a shop towel.

Clutch Inner & Outer

  • Bend the tabs of the lock washer back with a screwdriver and a mallet.
  • Hold the clutch inner, and loosen the center nut.
  • Remove the center nut and lock washer. 
  • Remove the clutch inner.
    • Make sure you remove the washer that sits between the clutch inner and outer; it will usually stick to the back of the inner.
  • Take this opportunity to check the clutch bearings by giving the clutch outer a good spin.
    • If the spin has rough spots or catches, you will need new bearings.
  • Remove the basket, bearings, collar, and washer.
4 - Bend Lock Washer Away From Nut
Bend the tabs of the lock washer back with a screwdriver and a mallet.
5 - Attach Clutch Holder
Hold the clutch inner, and loosen the center nut.
6 - Loosen Center Nut
Remove the center nut and lock washer.
7 - Remove Center Nut And Lock Washer
Throw Away The Lock Washer
8 - Remove Clutch Inner
Remove the clutch inner.
9 - Spin Clutch Outer
Take this opportunity to check the clutch bearings by giving the clutch outer a good spin.
10 - Remove Clutch Outer
Remove the basket.
11 - Remove Bearing
Remove the bearings.
12 - Remove Collar
Remove the collar.
13 - Remove Washer
Remove the washer.

Clean & Inspect

Your clutch takes a constant beating, and a thoroughly cleaned and inspected clutch can save you a lot of money, so don’t get lazy. You might find that the clutch pack is in good shape, or you could find a cracked clutch basket just waiting to break and destroy your engine.

If any component is damaged, worn out, or out of spec, you will need to replace it.

Clutch Release

  • You do not need to disassemble the clutch release mechanism for inspection.
  • Inspect the clutch release shaft gears for rounding, cracks, and chips.
  • Mesh the shaft and push piece and make sure the action is smooth.
  • The shaft seal should have no cracks or breaks.
  • The pivot spring should have plenty of tension.
14 - Inspect Clutch Cover And Arm
You do not need to disassemble the clutch release mechanism for inspection.

Bearings

If your clutch basket spun free on the shaft, your bearings and collar are ok, but give them a good cleaning and check for damage anyway.

15 - Inspect Bearings And Collar

Springs

  • Inspect the springs for bends or breaks.
  • Measure the free length of each pressure plate spring.
  • The springs should measure no LESS than 38.1mm.
  • Inspect the spring bolts for stripped threads and rounded heads.

16 - Measure Clutch Spring Free Length

Clutch Outer

  • Inspect the clutch basket for cracking and excessive grooving on the fingers.
    • My basket is fairly grooved, but it should last until my next inspection.
  • If your clutch basket is badly grooved, you can put off buying a new one buy grinding the fingers smooth, but that is a temporary fix.
  • Casting marks and hairline cracks look almost identical, so lightly sand down any marks to be sure.

17 - Inspect Clutch OuterPressure Plate

Your pressure plate is under constant stress, even when your bike is off, so take extra time cleaning and inspecting.

18 - Inspect Clutch Pressure PlateClutch Inner

  • Inspect the spring standoffs for bending or cracking, and inspect the body for excessive grooving.
  • As with the clutch outer, you can grind down the grooves, but again, that is a temporary fix.
  • My clutch inner will need to be replaced on the next service.

19 - Inspect Clutch Inner

Push Piece

  • Inspect the push piece teeth for rounding cracking and chipping.
  • Inspect the thrust bearing for smooth operation, and check the two washers for warpage.

20 - Inspect Push PieceClutch Pack

  • My frictions discs and clutch plates look almost brand new, so I’m going to clean then see if they are in spec.
    • If they are, I just saved $60.
  • Measure the friction and clutch discs, then check the clutch discs for the warpage.
    • The friction discs should measure no less than 2.7mm.
    • The clutch discs should measure no less than 1.2mm.
  • To check the clutch discs for warpage, you will need a sheet of glass and a post-it note.
  • Lay your clutch disc on the glass and try to slide the post-it note underneath.
  • The clutch disc warpage service limit is .05mm, but if your post-it note can slide underneath, it is probably out of spec.
21 - Meassure Friction And Clutch Discs
Measure the friction and clutch discs, then check the clutch discs for the warpage.
22 - Check Clutch Discs For Warpage
Lay your clutch disc on the glass and try to slide the post-it note underneath.

Clutch Install

You will need to lubricate every piece as it goes in. I use a break in lube and molybdenum grease for a few pieces, but the regular 10w-30 transmission oil and general-purpose grease will work fine.

Clutch Inner & Outer

  • Lube and install the basket washer.
  • Grease and install the collar, followed by the bearings.
  • Install the clutch basket.
  • Lube and install the inner washer, followed by the clutch inner.
    • Make sure everything spins free and smooth.
  • Install a new lock washer.
    • I am reusing this one because I will be taking this clutch apart a few more times before it goes in for good.
  • Install the center nut.
  • Install your clutch holder, and torque the center nut to 59 ft-lbs.
23 - Install Outer Washer
Lube and install the basket washer.
24 - Install Collar
Grease and install the collar.
25 - Install Bearing
Followed by the bearings.
26 - Install Clutch Outer
Install the clutch basket.
27 - Install Inner Washer
Lube and install the inner washer.
28 - Install Clutch Inner
Followed by the clutch inner.
29 - Install Lock Washer
Install a new lock washer.
30 - Install Center Nut
Install the center nut.
31 - Torque Center Nut To 59 ft-lbs
Install your clutch holder, and torque the center nut to 59 ft-lbs.

Clutch Pack

  • You need to coat every friction and clutch disc in oil, so place a shop towel or three under the clutch basket to catch the drips.
  • Get yourself a small tray or bucket to lubricate your clutch pack before install.
  • Starting with a friction disc, install your clutch pack with alternating friction and clutch discs.
32 - Lube Clutch Pack
Get yourself a small tray or bucket to lubricate your clutch pack before install.
33 - Install Clutch Pack
Starting with a friction disc, install your clutch pack with alternating friction and clutch discs.

Pressure Plate

  • Before installing the pressure plate, fold the tabs of the lock washer out against the sides of the center nut.
  • Lube and assemble the push piece, with the thrust bearing between the two washers.
  • Place the push piece in the pressure plate and place the pressure plate on the clutch inner.
  • Install the clutch springs and spring bolts finger tight.
    • I do not recommend using an impact driver for this step.
    • You will need to push the bolt head against the clutch springs while you thread the bolts.
    • If you use a driver, you could easily strip out the standoffs.
  • Tighten the bolts in a criss-cross pattern, then torque in the same criss-cross pattern to 88 in-lbs.
    • You can jam the clutch outer and crankshaft gear with a screwdriver to keep the clutch from turning. 
    • 88 in.-lbs against these gears won’t hurt anything.
34 - Bend Lock Washer Tabs Against Nut
Before installing the pressure plate, fold the tabs of the lock washer out against the sides of the center nut.
35 - Assemble Push Piece
Lube and assemble the push piece, with the thrust bearing between the two washers.
36 - Place Push Piece In Pressure Plate
Place the push piece in the pressure plate.
37 - Install Pressure Plate
Place the pressure plate on the clutch inner.
38 - Install Clutch Springs
Install the clutch springs and spring bolts finger tight.
39 - Install Spring Bolts
I do not recommend using an impact driver for this step.
40 - Tighten Spring Bolts
Tighten the bolts in a criss-cross pattern.
41 - Torque Spring Bolts To 88 in-lbs
then torque in the same criss-cross pattern to 88 in-lbs.

Clutch Cover/Lever

  • Rotate the push piece teeth to align with the shaft teeth.
  • Install the cover with a fresh gasket and with the lever facing the rear of the bike.
    • You may need to install the cover a few times to get the clutch lever just right.
  • Yamaha has the clutch cover bolts speced to 88 in-lbs, but I don’t recommend it.
    • For whatever reason, these bolts will shear off if you try to torque them to spec.
  • Instead, tighten them as much as a ¼ ratchet will let you.
42 - Install Gasket And Cover
Install the cover with a fresh gasket and with the lever facing the rear of the bike.
43 - Tighten Cover
Instead, tighten them as much as a ¼ ratchet will let you.

You can follow me at Fix Your Dirt Bike across all social media, and If you have any questions, please let me know in the comments or direct message.

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Video: How To Fix A Crack In Your Plastic Gas Tank

How To Repair A Crack In The Plastic Gas Tank On Your Dirt Bike

Cracking your gas tank sucks twice; first, you get stranded, then you have to get a new tank.

If you have a metal tank, no problem, hose it out and weld it back together. If you have a plastic tank, your options are limited.

Long story short, JB weld PlasticWeld does not work. It was only $8, I was in a hurry, and I could get it locally, so I gave it a shot. I was suddenly no longer in a hurry for round two, so I had time to fix my tank correctly.

My go-to is the Blue Magic Quiksteel Plastic Gas Tank Repair Kit, which you get here if you don’t have one yet. I’ve never had to repair a crack this bad, but I’m not too worried, this stuff is really good.

You can see the Step-By-Step Guide Here.

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How To Fix A Crack In Your Plastic Gas Tank

How To Repair A Crack In The Plastic Gas Tank On Your Dirt Bike

How To Fix A Crack In A Plastic Gas Tank - FeaturedCracking your gas tank sucks twice; first, you get stranded, then you have to get a new tank.

If you have a metal tank, no problem, hose it out and weld it back together.

If you have a plastic tank, your options are limited.

Long story short, JB weld PlasticWeld does not work. 

It was only $8, I was in a hurry, and I could get it locally, so I gave it a shot.

I was suddenly no longer in a hurry for round two, so I had time to fix my tank correctly.

1 - JB Weld PlasticWeld Does Not Work For Gas Tanks
Long story short, JB weld PlasticWeld does not work.
2 - PlasticWled Must Not Be Rated For Fuel
It was only $8, I was in a hurry, and I could get it locally, so I gave it a shot.

Plastic Gas Tank Repair

This tank is off my 2001 Yamaha YZ125 project bike, and it has a crack on both sides. The right side crack is relatively small, but the left side crack is on the body line, and I can almost stick my pinky through it when It flexes.

3 - The Right Side Crack Is Fairly Small
The right side crack is relatively small.
4 - I Can Stick My Finger Through The Left Side Crack
The left side crack is on the body line, and I can almost stick my pinky through it when It flexes.

My go-to is the Blue Magic Quiksteel Plastic Gas Tank Repair Kit, which you get here if you don’t have one yet. I’ve never had to repair a crack this bad, but I’m not too worried, this stuff is really good.

 

Quicksteel Plastic Gas Tank Repair KitGas Tank Prep

  • Wash your tank to remove as much dirt as possible.
  • Follow that with a wipedown of acetone to remove any fuel reside.
  • The Quiksteel kit provides a small piece of sandpaper that I’m guessing is about 60 grit, so they mean it when the instructions say deep grooves on the tank.
  • Sand the area around the crack in two directions to get a consistent crosshatch pattern for the putty to adhere.
  • Follow that with a rub down of denatured alcohol.

Quicksteel Gas Tank Repair Putty Application

  • I can never guess how much putty I need, so I started with about a quarter stick for the smaller crack.
  • Work the putty until it starts heating up and changing color.
    • The instructions say it will turn a different shade of white, but I can never tell the difference.
    • However, you definitely won’t miss the heat!
  • When your putty gets hot and starts leaving residue on your hands, it’s good to go.
    • I recommend wearing gloves, I don’t know what it will do to my hands, and I don’t want to find out.
  • You will have about 5 minutes to work the putty, and you will feel it stiffening as you go.
  • This putty cures in an hour, but I usually let it sit overnight.
  • Once the Quiksteel putty cures, you can sand off the high spots, but be careful not to sand down to the crack you just fixed!
5 - Work The Putty Until It Gets Hot And Leaves Residue On Your Gloves
Work the putty until it starts heating up and changing color.
6 - Apply Enough Putty To Cover At Least One Half Inch On Each Side Of The Crack
When your putty gets hot and starts leaving residue on your hands, it’s good to go.
7 - You Have About 5 Minutes To Work The Quiksteel Putty
You will have about 5 minutes to work the putty, and you will feel it stiffening as you go.
8 - You Will Feel The Putty Harden As You Work It
This putty cures in an hour, but I usually let it sit overnight.
9 - You Can Sand The Quiksteel Plastic Tank Repair Putty After One Hour
Once the Quiksteel putty cures, you can sand off the high spots, but be careful not to sand down to the crack you just fixed!

I’m not going to bother sanding my tank because at this point, I just… eh, it holds gas.

This Quiksteel Plastic Gas Tank Repair Kit works great, but it never looks great, and my plastics will never sit flush to the tank. 

BUT, I can live with that considering this repair kit costs $15, and a new tank is over $200!

New IMS Gast Tank For 2001 Yamaha YZ125

You can follow me at Fix Your Dirt Bike across all social media, and If you have any questions, please let me know in the comments or direct message.

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Video: 1994 – 2001 Yamaha YZ125 – Ignition System Troubleshooting And Testing

How To Troubleshoot & Test The Ignition System On Your 1994-2001 Yamaha YZ125

Electrical troubleshooting can get very frustrating, and it’s very easy to lose track of what you’ve done and still need to do, so write down everything you need to test, then as you go, write down the test results.

You want to start with the simplest solution; there’s no sense replacing the stator when all you had was a ground fault. 

So start with the spark plug, then work your way back to the stator.

You can only test the CDI through the process of elimination, so if everything else is tested within spec, the CDI will need to be replaced.

You Can See The Full Step-By-Step Guide Here.

For whatever reason, Yamaha does not provide peak voltage specs for anything, so If you want to do a physical test of your ignition coil, you will need to take it to a shop and have it tested.

Here’s a link to open the YZ125 Electrical System Specifications in a new window.

You will need a multimeter if you get to the ignition coil and stator. If you don’t have a multimeter yet, you can get one HERE.

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