The International CBX Owners Association

Hey guys,

So my bike smokes on startup. Sometimes a bit, sometimes a bunch, but it always tapers off when it gets warmed up.

I think I understand that this would tend to implicate the cylinder head, and could be as simple as valve seals, and as un-simple as valve guides or valves not sealing well.

Please do me a favor and run through the proper sequence for diagnosing this One More Time?

Last: How likely is it that a new set of seals would make it all better? And could this job be done without removing the head?

N.

If it smokes only at start-up after a longer parking period, I wouldn't necessarily worry too much.

Saying with certainty whether it is due to valve seals or guides is difficult if not impossible. Although, if it smokes equally out of both exhausts, it is most likely valve seals as they are the part that goes bad with time and usually all at the same time. A poor valve seat can be diagnosed with a compression or leak-down test.

And as responded to in your "Projects" thread, replacing seals or guides with head installed is almost impossible, in my opinion.