Smokes a bunch when first started.

[JP400ex]

My bike smokes quite a bit for the first 30-60 seconds after i start it. One person told me this is pretty common with the 400ex motor and that it is the valve seal. Does this sound right?

[Pappy]

how many hours are on the engine? valve seals is a could be. what color is the smoke?

[JP400ex]

Not sure how many hours on the engine... the smoke is a light blue. The engine has a ton of upgrades though.... 10:1 weisco piston, 416 kit, ported

[Aceman]

Replace your valve seals.