Re: Valve clearance questions dohc

Posted by Tjhill on
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Valve-clearance-questions-dohc-tp4038374p4062713.html

Here's an odd one for you all. Now, I'm new to this thread, and I just bought a 1982 CB900C. I'm somewhat new to the bigger CB's. The guy I bought it from put in new shims, but gave up when, after putting in the shims the motor would only crank about 350 degrees back and forth as if the #3 piston is hitting something at TDC. I removed both cam shafts in case he overshimmed, but it still wasn't quite hitting TDC. The odd thing is that the right hand exhaust valve on the #3 seems to be actually sitting higher than all the rest of the valves, so visually that looks like the problem. When hand cranked though, the clunk when the crank stops sounds like it's maybe at the chain from the crank to the primary. Not looking for online diagnoses, just wondering if anyone else has had an issue like this, and if they may know where to start other than obvious "tear the top end off and see if that valve isn't seating properly". Also does it seem wiered that one valve would be sitting higher than the rest? I mean, if it were holding a piston off TDC, shouldn't it be lower?

Thanks sorry about the high-jack, more meant as a segue!