Oil the bushing that is located in the sprocket at least every two (2) hours of driving time. You’ll have to oil the clutch even more often if you have small children, riding in a small area, never going fast enough to engage the clutch all the way. The clutch continues to generate heat until it engages.
Oiling the clutch is extremely important. If heat damage occurs, the clutch will never disengage and the machine will start taking off by itself as soon as you start the engine. This is very dangerous! You can see heat damage inside the clutch drum, the metal turns from black to a blue color. The clutch must be replaced if it has heat damage and won’t disengage. Heat damage is never covered by warranty.
Where do you oil the clutch? Behind the snap ring, next to the sprocket teeth at the end of the clutch. There’s an internal bronze bushing behind the snap ring that requires lubrication and it’s up to you to put it there each time. With the engine off, squirt several drops of oil behind the snapring while the bushing is warm. You can also oil the clutch before you ride, oil the clutch and give the oil a few mintues to penetrate down into the bushing. If you don’t give the oil time to get down onto the bushing, the oil will just fling off, which is the same as not oiling it at all because the oil never reaches the bushing at all. What oil should I use? A good automotive oil like 10W30 or a straight 30 weight oil is perfect. It’s a good idea to oil the chain at the same time. If the chain gets kinky from lack of oil it should be replaced before it damages the clutch sprocket. A new chain is cheaper than a new clutch.
The clutch is an automatic transmission that is activated by the increased rpm of the engine. The clutch should not engage when the kart is at idle. The engine manufacturer sets the idle speed of an engine at the factory. The idle speed of the engine is normally around 1,650 rpm +/- 200 rpm. There are several things that can cause the clutch to engage at idle. Because the kart manufacturer does not start each kart after assembly, it’s important that the dealer or the kart owner take a couple of minutes to read the owner’s manual and review the recommended procedure when starting or servicing a new kart.
Throttle linkage can bend while riding or in transit to the dealer. It is highly recommended to always start the go kart with the rider sitting in the drivers seat with his or her foot on the brake pedal. Make sure they know which foot pedal, the one on the left, is the brake versus the gas pedal. If the driver has to start his/her own kart then place the front end of the kart against a stationary object like a tree or fence post. Once in the kart, you can roll it backwards with your hand or foot to get the kart in a position to drive forward.
During assembly at the kart factory it’s possible that too much tension was placed on the throttle linkage causing the engine to idle above 2,000 rpm (the starting speed of the clutch for engagement). Think and stress safety. When you start the go-kart, be in a position where you can shut it off if the clutch wants to engage by itself. Most karts have two shut off switches on them, one on the steering column or steering wheel and the other on the engine itself. Another possibility is to pull off the spark plug wire, which might give you a slight shock.
A Tachometer can be used on the engine to verify just where the engine idle speed is set. You can’t verify the correct rpm by listening to the engine and concluding it is too high or too low.