The term Right Stuff has been used to describe both human and product characteristics in many different ways, but I can’t think of one more fitting to motorcycles than the engine case sealant made specifically for the job of sealing crankcases.

Whether it’s Honda Bond, YamaBond, ThreeBond 1184 and 1104, or some wonderful stuff from Suzuki’s parts counter #1207B Gasket bond – these all are the Right Stuff. You will not go wrong with any of the products shown here. Proper engine case sealers like these are much thicker, they stick to the narrow engine surfaces better, and they do not deform and move away from pressure like the auto sealers, RTV, and Silicone does when tightened during assembly.

I’ve been taking engines and case covers apart for 40+ years. The #1 mistake that I’ve seen in hundreds of previous repairs is the use of Silicone, RTV, or other types of automotive liquid or squeeze-tube sealers to assemble cases and covers. The Permatex RTV Silicone that you use at the ends of your car/truck’s intake manifold is NOT the sealant that you should use when assembling your motorcycle’s engine cases. The formulation, the consistency, and the amount of “Solids” carried in the sealant are not the same.

Look closely at the Black RTV Silicone on the cases of our Yamaha TTR225 project’s engine. You’ll notice that the sealer was pushed (squeezed) away from the very surfaces it was supposed to “seal”. The person doing the reassembly used the Wrong Stuff. Not only are the case surfaces not sealed and were leaking oil in multiple places, the loose strips and large pieces of RTV Silicone squeezed away are all over the inside of the engine – just waiting to be pushed through the oil supply and cause blockages and major failures.