Although it only has 15k miles on the clock, it has sat for 22 years, all the last owner said was that the camchain was noisy - this is a common problem with them, so I found out. So I proceeded to change the cam chain and obviously a visual inspection with the head off confirmed there was very little wear on the bores. Boxed it all up, got it running and away it went, after a minute or so it started smoking, bad grey blue smoke.
So, in a nutshell, I changed the valve stem oil seals, no change, new exhaust valve guides, no change, bore de-glazed, no change, new piston rings, no change. It still smokes as if I'd never done anything to the bike. makes me think that the last owner wasn't telling me the whole story.
I'm just about to take the engine out of the frame for the
th time. I am going to check the cylinder head for cracks/warping and double check the bore sizes (I have heard of Haynes Manuals being incorrect on old 750 Hondas), I am beginning to think the engine had half a rebore. The biggest clue is that the compression is uniform at 120psi on all 4. It has always been around this value. I wasn't too worried - being truthful I just wanted to get it running to sell the bike. Now that I've spent so much time on it I probably will keep it some more - the engine is beautiful when it runs.Anyone had anything similar?
