Your Kart or mini-bike is equipped with a centrifugal clutch that has to be lubricated daily. Get into a maintenance program with your Kart. When you add gas – oil the clutch, when you check the oil level in the engine – oil the clutch, when you are finished riding – oil the clutch while it is still warm before you put it away. YOU CAN NEVER OVER OIL THE CLUTCH. Both the clutch and the chain need daily lubrication.
The clutch contains an oil impregnated bronze bushing. 15% of the weight of the bushing is the oil that is impregnated into the bushing by the manufacturer. This oil can leak out, or can evaporate over time, and must be replaced. The bushing is press fitted into the sprocket and rotates around a steel sleeve held together by a snap ring.
With the engine off, apply oil (30 weight or 10w30 motor oil) to the snap ring area. DON’T USE A SLICK 50, ENERGY RELEASE OR DYNAMITE because the special additives in these oils prevent the required steel to steel contact between the clutch shoes and the clutch drum. To make it easier for the oil to work its way into the bushing, manually roll the Kart along while applying the oil. The rear of the Kart can also be raised permitting the rear wheels to rotate freely for this lubrication procedure. FOR THE BEST RESULTS, OIL EVERY TWO (2) HOURS OF RUNNING TIME. One squeeze of oil from a squirt can applied to the snap ring while the clutch is warm is ideal.
Dirt and sand are abrasive and can act like sandpaper to prematurely wear the bushing, the sprocket, the chain, and other parts of your Kart. Since Karts are driven on all kinds of terrain, it’s often hard to keep the moving parts dirt free. A clean Kart can prolong the life of the clutch’s bushing and sprocket as well as the chain. Try wiping or brushing away as much dirt as possible from these areas after each use of you Kart.
If you find that the drum and sprocket assembly wobbles on the engine shaft, this indicates that the bushing is wearing out. You should buy a replacement bushing before you cause damage to the sprocket or sleeve with steel to steel contact. A worn bushing can also lead to a thrown chain. Replacing the bushing early when you first see a wobble will prevent damage to the clutch. Preventive maintenance is the secret to prolonging the life of the clutch.
Problems leading to premature clutch failure and preventative measures.
- Poor lubrication of bushing – oil the clutch frequently.
- Riding the brake and gas pedal simultaneously – one or the other never both together, this generates too much heat and vaporizes the oil in the bushing.
- Short stop and go runs – the longer the run, the easier it is on the clutch.
- Chain too tight – chain should have some flex to it – ½” is ideal.
- Misalignment of sprockets – clutch and rear drive sprocket must be on the same exact plane.