No Exploding Clutches! Stop Burning Belts! Service Torque Converter NOW!

In this Official Service Bulletin (OSB), you will learn how to properly service the Torque converter, or main clutch on your Trailmaster Mid Size go kart. This applies any mid size kart, including the Trailmaster Mid XRS, Mid XRS, Mid XRX-R and the Blazer 200R. In addition, you may also find this helpful if you have other branded karts with a 30 series torque converter!

Why service the clutch on a mid size kart?

First, there are several reasons you might want to service your clutch. If any of these apply to you, go ahead and perform this service.

• After the first few hours of initial break-in time on a new go kart
• Roughly every 10 hours of riding time
• If the kart hesitates upon take-off
• if you feel that the kart has lost some of its power
• if a belt is burning or breaks
• any time you change the belt due to normal wear and tear, or if you upgrade to a performance belt

This is a good service to perform if your kart doesn’t have the power or responsiveness that you expect. If you press the gas and the kart hesitates to take off, or if you’re not getting the full power that It used to get, go ahead and service the clutch.

Find a good belt for your mid size kart before your start the service

Before moving on, you can find the performance belts at GoKartMasters.com:

Mid XRS: here

Mid XRX: here

Blazer 200 (without reverse): here

Mid XRX-R (with reverse): here

Blair 200R (with reverse): here

Get start on your Mid size kart clutch service:

Begin at the rear of your kart, identify the CVT cover. It is a black plastic cover. First, remove the bolts that hold it in place. There is one bolt at the bottom, one bolt that goes through a bracket and into the side of the engine, and one bolt toward the front of the engine with a spacer on it. 

Next, pull the plastic cover off the expose the CVT. The front clutch, or driver, is the round silver contraption that the belt goes around, closer to the front of the kart. 

Mid XRS and XRX models will have a bronze bushing. This can be replaced with the bearing version but will require switching to the belt for the reverse model and may become confusing in the future.

Mid XRX-R and Blazer 200R will have a silver bearing as shown below.

To complete the next step, remove the bolt that runs through the center of the driver with a 10mm socket. 

Next, take out the black slotted washer and the outer half of the clutch. 

Then, remove the belt if you are replacing it. We recommend a USA mad performance belt.

Finally, open up the silver housing of the clutch that you took off of the kart. Continue to process b separating the slide collar from the center of the silver casing. At this point you should have 2 silver housing pieces, a black slotted washer and slide collar with 4 bumps around the outside. 

Clean the components of your mid size kart clutch

Thoroughly clean all of these pieces with brake cleaner. Makes sure you clean all surface, including where the slide collar rides on the center opening. 

Now you can apply a thin layer of grease over the slide collar.

Reinstall the clutch on your mid kart

Finally, you’re ready to reassemble the pieces of the clutch. Pay close attention that the flat end of the collar goes against the silver housing piece that will be closest to the belt. The other end has a rectangular shoulder. You’ll notice that the rectangular shoulder will fit snugly inside the hole of the silver housing that is facing away from the engine. If you do not install this correctly, the slide collar will be able to move freely rather than being locked into place. Your clutch may work temporarily but it will eventually stop working and possible even explode.

Install a new belt onto your kart by placing the belt over the rear pulley first. Make sure the the flat side of the belt is toward the engine. The angled edge should be facing away from the engine. Slide the belt over the center shaft of the front clutch. If your clutch has a bronze colored bushing, clean the bushing with brake cleaner and apply a thin film of grease before installing the belt.

Pay close attention to signing up the parts of your clutch!

Pickup the entire silver housing assembly and slide it over the center shaft, aligning the key on the shaft with the keyway inside the slide collar. Make sure the shoulder of the collar stays in the correct position in the housing. Install the slotted washer, making sure the slot slides over the key on the slide collar.

Tighten the clutch bolt with an impact, but don’t over tighten. 

Replace the plastic cover and tighten all of the bolts back down.

This service is recommended every 10 hours, any time you lose power, or anytime you change the belt.