10 Things to Know about a Centrifugal Clutch

How does a clutch work?

A clutch is a form of an automatic transmission that engages when the RPM of an engine reaches a certain threshold. Clutches should not engage when the engine is idle – typical idle speeds are around 1650 RPM.

How do I avoid heat damage?

You can avoid heat damage simply by ensuring your clutch is properly oiled. When a clutch has been damaged by heat it will often fail to disengage, causing your machine to start moving as soon as the engine is started. This type of damage can frequently be seen inside the clutch drum where the metal will turn from a black to a blue-ish color. The only solution for this type of damage is to replace the clutch.

How do I oil clutch bushings?

When in use, you must frequently oil the bushing located in the sprocket. A good guideline is at least once for every two hours of use. If you're using the clutch in such a way that it is not fully engaging then you will likely need to oil the bushing more often – this is most often the case when cruising at lower speeds.

How do I oil the clutch?

In the clutch there is an internal bronze bushing that requires lubrication. This bushing is located behind the snap ring, next to the sprocket teeth, at the end of the clutch. To lubricate this bushing, ensure your engine is off and squirt several drops of oil behind the snap ring while the bushing is still warm.

Which oil should I use?

An automotive oil like 10W30 or a straight 30 weight oil is ideal.

Should I lubricate the crankshaft?

If your machine has a grease fitting in the crankshaft then you can put a shot of grease once a month for adequate lubrication. 

How does your chain affect the clutch?

Too tight of a chain can put friction on the bushing or bearing which may cause the clutch to engage while the engine is idling. Chains will also loosen with time, when this happens you should move the engine to reduce the slack in the chain. Leave about ½'' of play between the top and bottom of the chain, being careful not to over-tighten. Also keep an eye on the sprockets, making sure they're perfectly aligned, a bad alignment can cause the chain to pop off or unevenly wear the sprockets.

How long will my clutch last?

If installed and maintained properly a clutch should last several years. If abused or mistreated, a clutches lifespan can be considerably shorter.

Driving Habits that shorten a clutches lifespan

• Driving too slowly - at low speeds the clutch will not fully engage causing heat build-up which could lead to heat damage.
• Stop-and-Go driving - the clutch needs time to cool off after engagements.
• Keeping a foot on the brake
• Using tires too large for the clutch
• Exceeding the weight limit of the clutch
• Restricting the carburetor or gas pedal travel - these methods cause clutch slipping which is damaging to the clutch.