The key to the performance of your motocross bike is in the clutch. You may be an ace as a motocross player, but if your clutch isn’t doing its part, you may find it difficult to control your engine. The following are some tips for a great clutch.
First of all, take out those factory clutch springs and replace them with stiffer ones. Bicycle factories never use top-of-the-line parts when assembling the clutch. High-performance parts often cost more money than those used by factories. But keep in mind that you don’t have to change every spring. Usually two or three will do, but you can experiment with what works for you.
Don’t neglect your transmission oil. It’s not the same as cars and trucks where you can only change the oil once a year. Ideally, your oil should be replaced every two to three races. It may sound like a lot to you, but an oil change is cheaper than a transmission overhaul. Remember that the dirt you pick up on the track builds up and will put early pressure on your clutch discs.
Always carry extra shims for emergencies. You never know when you’re going to need these things. It can happen in the middle of a race and you won’t be able to remedy the situation. You can simply insert the washer right under the bolt. The added thickness will preload your springs and eliminate that spongy feeling in your clutch.
You can top off your transmission to the proper level with automatic transmission fluid, that is, if it’s compatible with GM. But don’t use a Ford-type fluid. The difference between the two is that the GM fluid grips better than a Ford fluid which is slippery like molasses.
Never use factory installed aluminum clutch plates. These plates are suitable for regular use only, but not durable enough for extended motocross use. They don’t hold up as well as steel plates, which are heavier but more durable. There are two disadvantages to aluminum plates. First, they wear faster than steel, leaving metallic deposits in the oil, which accelerates mechanical wear. Two, aluminum warps easily when subjected to the extreme heat generated in motocross.
Aged plates build up a layer of enamel on the surface which makes them slip more noticeably. When you notice this slippage, remove the fiber clutch plates and sand the surface to remove the slippery polish. Reinstall after cleaning.
Make sure the clutch lever is not too tight. Adjust it so that a quarter can slide between the lever perch and the lever without catching the clutch cable.