sanoke
New member
I was riding my 2019 C400X when suddenly there was a loud clattering noise and a lot of blue/white smoke coming out of the tail pipe. The engine froze up and I had to have it towed to the dealer. Turns out it swallowed an exhaust valve. The problem was that the bearing for the rocker arm roller for the exhaust valves had worn to the point where the valve shim fell out. This caused rocker arm to press on the valve retainer instead of the valve stem. That caused the valve keepers to fall off and allowed the valve to fall into the combustion chamber. Fortunately I had an extended warranty so I got a new engine out of the deal.