Sandpoint, ID_**Honda CRF250Rs have a reputation for chewing through intake valves, especially the one on the right-hand side, even if you stay up on the maintenance of the air filter. The rate at which my Honda was requiring intake-valve adjustment was getting ridiculous. Even after switching to Kibblewhite stainless steel intake valves I was only getting 10 to 15 hours out of a valve adjustment. A set of Kibblewhite valves lasted me less than a year. The problem was that the top cap of the carburetor (where you access the slide and jet needle) had come loose and was allowing dirt to freely enter the intake tract. Seeing how much dirt was getting in through the carb top cap literally made me sick to my stomach. To fix the problem I cleaned the carburetor, then simply ran small beads of RTV around the seal on the top cap and the seal in the small access cover in the cap. Problem solved! Silicone sealant is affected by gasoline or oil, so don't get any inside the carburetor."Got a Trail Tip? Send it and some pictures to firstname.lastname@example.org, subject: Trail Tips."