question on Valve specs for those who have worked on them
Posted October 03, 2000 - 05:19 PM
Also when you measure the clearance it is very difficult to slide the feeler guage into the gap at a straight angle. You end up coming down at a sharpe angle and in my case the feeler guage seems to bind up a little until you get it under the cam lob. Then it seems to free up a little. This makes me think that one size larger feeler guage would fit if you could slide it in at a straight angle. Did anyone else experiance this or am I just getting way to particular.
sorry about the long e-mail and thanks for the help.
Also just an FYI my exhaust vales were both measured at .203 snug and .229 tight on a spec of .25 to .3. Both of these will get a one size .05 larger shim.
It has been an entire year of riding on these measurments.
Posted October 04, 2000 - 06:00 AM
My exhaust valves also tightened up a bit quicker than intake but that makes sense to me.
I didn’t have to face quite the dilemma you are, it sounds like your intake clearance is pretty close. If forced to choose I would opt for a bit loose over a bit tight. On the other hand your clearance does fall within spec in the strict sense so I wouldn’t worry about riding it like that either. I’m no help at all am I?
Posted October 04, 2000 - 06:32 AM
Posted October 04, 2000 - 11:06 AM
My 426 was making noise that I originally assumed was valvetrain (it sure sounded like it) but turned out to be coming from somewhere else. Fire it up and stick your ear down there and see if you can’t determine the area of the motor responsible for the noise. Someone (Matt Porritt?) here suggested holding one end of a piece of steel pipe against your ear and the other against the motor as sort of a moto-stethoscope to detect the source and maybe cause of engine noise. I haven’t tried this but it sounds like a good idea.
If I were convinced the noise emanated from the head I would check the chain tensioner and the cam chain tension. The manual also describes the wear limits of the cam chain. I doubt this would have happened but maybe the tightening valves have resulted in an overly taxed (loose and stretched) cam chain.
I hope its nothing serious.