My drive sprocket keeps sliding to the side and then my chain pops off on my go kart. How can I fix that; can you help me?
The sprocket is sliding because the set screw in the hub of the sprocket is either lose or gone. Tighten it down and it will keep the sprocket from moving. A poor mans fix is to use two hose clamps put on either side of the sprocket, to keep it from moving left and right.
The same trick can be used for brake discs. In the case of the brake disc you want it to move, but not lose the key. So the key is cut long, so that the disc has room to move left and right. The hose clamps are mounted on either side of the key (if there is room.) The proper way is to purchase some shaft collars and mount them to the shaft, or substitute a bolt for the lost set screw.
In the How To Build a Go Kart series we discuss in the Book 201 and 302 how to tackle drive systems problems, such as chains popping off and how to make optimal drive lines for rock solid performance so the chain does not pop off!