Is your dirt bike clutch slipping? It might be time to replace it. Maybe it just needs a simple adjustment. Learn what the most common clutch problems are, what actually causes them, and how to fix and prevent it.
Learning how to use the clutch on a dirt bike is more than just an essential skill. If you become proficient in clutch control, riding will be easier, and more fun and your overall skill and speed will likely increase.
This means that having a properly working clutch is extremely important. A little bit of clutch slippage or drag is not only annoying, but it also makes learning to ride and improving your technique so much more difficult.
What Is A Clutch On A Dirt Bike?
A dirt bike clutch is an assembly of a basket holding metal discs and friction plates that spin and either slide (spin) across each other or compress and rotate together. These actions control how the engine spins the transmission.
A clutch is used to get the bike moving while in gear. It is also used to spin up the engine RPM by “slipping” the clutch to put more power into the transmission and accelerate faster.
Do All Dirt Bikes Have A Clutch?
Not all dirt bikes have a clutch. Some small kids dirt bikes only have a 1-speed transmission or gearbox. A semi-automatic transmission has multiple gears but there is no manual clutch to control the RPM input to the transmission.
Most motocross and enduro bikes have a clutch. The easiest way to tell if a dirt bike has a clutch is to look for a clutch lever on the left side of the handlebars. It will look the same or similar to the front brake lever that’s on the right side of the bars.
How Do I Know When To Replace My Clutch?
There are a number of signs that will tell you when the clutch may need to be replaced. But, just because there’s one of these symptoms doesn’t mean it needs a full rebuild.
Always remember to start troubleshooting with the easiest things first, such as making sure everything is adjusted properly and within factory spec.
Most common signs you might need a new clutch:
- Clutch slipping
- Clutch grabbing
- Feels like bike lost power
- Clutch lever action is notchy
- Clutch smells burnt
- No more clutch adjustment
- Clutch is hard to pull in
What Is Clutch Slipping On A Dirt Bike?
Clutch slipping is when the clutch is partially engaged so the bike will move but the engine RPM will spin faster than the transmission would if the clutch were fully engaged. Slipping the clutch is used to start riding from a stop, but it can also be a symptom of a worn out clutch.
How To Tell If Clutch Is Slipping
An easy way to tell if your clutch is slipping is to ride the bike in 3rd or 4th gear at a speed just above idle then quickly twist the throttle wide open. If the RPM quickly jumps up at any point without accelerating then the clutch is slipping.
What Causes A Dirt Bike Clutch To Slip?
There’s several things that can cause a clutch to slip. The most common reasons are:
- Clutch cable out of adjustment
- Clutch fibers are worn
- Clutch fibers are old and hard/glazed
If your clutch is slipping, first check the adjustment of the clutch cable and/or lever. There should be a small amount of slack when you pull the lever in to disengage the clutch.
If the clutch is still slipping, it may be time to take the clutch cover off and pull out the fiber discs to check for wear.
What Is Clutch Drag?
Clutch drag is when the clutch doesn’t fully disengage and is trying to power the transmission to make the bike start accelerating. An example of this is when you pull the clutch in, shift it down into first gear and the bike wants to start moving forward.
What Causes Clutch Drag
There’s a number of things that can cause a clutch to drag. The possible reasons why are:
- Clutch is sticking/not warmed up yet
- Cable out of adjustment
- Hydraulic clutch has air in system
- Warped clutch discs
- Wrong clutch fibers
- Notched clutch basket
- Wrong transmission fluid/oil
What Is A Notchy Clutch Feeling?
A notchy clutch is when you pull in or release the clutch lever and it’s an inconsistent feel that is not smooth. It will move and then feel like it “catches” on something and then gets past it and moves again.
What Causes A Notchy Clutch?
A notchy or inconsistent clutch feel is usually caused by worn grooves in the clutch basket or a kinked clutch cable.
To fix a notchy clutch feeling, first check the cable for kinks or any spots that are worn. If the cable is in good shape and has a smooth route to the clutch, then you may have to crack open the clutch cover.
If you see grooves from the fiber plates on the clutch basket then it's time for some maintenance. You can usually file/sand the grooves down if they're not very deep or it's your first time doing it. Otherwise upgrading to a heavy duty clutch basket may be a good idea if you're a "clutch abuser".
Why Is My Dirt Bike Clutch Lever So Hard To Pull In?
A stiff clutch is a pain, literally. Even if you have strong hands, a clutch lever that is hard to pull in will wear you out if you use the clutch a lot.
There's a number reasons why your clutch could be hard to pull in. The most common problems are a worn or dried out clutch cable, dry/corroded clutch pivot bolt, a kinked clutch cable, stiff clutch springs, or a notched clutch basket.
How To Make Dirt Bike Clutch Easier To Pull In
The most important factor to keeping a smooth and light pulling clutch lever is the regularly lubricate the clutch cable. This is, of course, assuming that your clutch is actually cable operated.
We'll look at a hydraulic clutch in a minute. A clutch cable is inside of and rubbing against a plastic tube. There is going to be friction, so you want to reduce it as much as possible.
Reduce Friction; Increase Clutch Cable Life
Think of the tube that the cable is in as a water-slide and the cable as you going down the water-slide. If the slide is dry, you're not going to slide down very well.
There will be a lot of friction and you'll very slowly slide down. Once you add the "lubricant" of water to the slide, you will slide down much quicker with less friction. This goes the same for a clutch cable.
Using a clutch cable lube (Amazon) on a regular basis will keep your clutch cable slippery smooth and easy to pull, as well as increase it's lifespan.
Clutch Perch That Uses Science of Physics
Adding a different leverage point on the clutch lever can change how hard you have to pull. Outlaw Racing's EZ pull clutch lever has 3 positions so you can increase the leverage that will make it easier to pull in the clutch.
This is a simple and effective way to fix a stiff clutch. I only recommend this after you've tried lubricating and/or replacing your clutch cable with a new unit.
Also, due to the fact that you're changing the leverage, the range of clutch pull will change. This means that you will have to pull the clutch lever in further to fully disengage the clutch.
If the clutch is dragging, trying adjusting the perch position. Remember to leave a small amount of play in the cable or else your clutch may not be fully engaged and start slipping.
Hydraulic Clutch - Good or Bad?
Hydraulic clutch kits are available and gaining popularity, but why? They offer a softer clutch pull, and there is no cable to break or adjust.
Yes, the kit is an investment, but it may be worth it if you are seeking the lightest clutch pull and your stock cable clutch isn't cutting it.
There's got to be downfalls, right? It's definitely not cheap, but for under 300 bucks how many other mods can you do that make a major impact on your riding?
Being hydraulic, the line is susceptible to leaking or air entering the system, which has to be bled out. These are trade-offs that you will need to consider when deciding to keep the cable or convert to a hydraulic clutch.
How To Make A Clutch Last Longer
There are many ways to make a clutch last longer. The most effective way is to only use the clutch to get the bike moving in first gear. However, as you gain riding experience and skill you'll realize that learning to use and control the clutch can help you ride faster and more efficiently.
The best ways to make a dirt bike clutch last longer are:
- Learn proper clutch control technique
- Use the right kind of oil
- Change your oil often enough
- Shift into neutral when stopped
If your clutch needs to be replaced, do not worry. Clutch parts are relatively inexpensive, and it really isn’t that hard to do in your garage. For step by step tips and pictures on how to replace your dirt bike clutch read more here.