Spring is finally here for us in Canada and i started up the beast (2000 yz426) and to my amazement it vomited large quantities of thick grey-blue smoke, I had the neighbourhood kids running in fear it was so bad. Anyways i figured it was my valve oil seals because it smoked a bit last season on start-up. This will be my second time replacing the exhaust
valve oil seals in the past 2 years they seem to be over heating and burning up i think
. The carbs good and valve clearances are in spec. timing according to the cams is good although from the appearance of the valve faces and exhaust id say it was a little on the rich side. I ride mostly trails so im thinking i need to open the throttle up more to clean out the carbon. I use 94 octane fuel because anything lower than that makes pinging.This is a cheap repair but very time consuming, any help would be apprieciated.
P.S. I know there is a valve missing.... valvespiston exhaust portintake port