Honda-SOHC

SOHC.co.uk Forums => CB500/550 => Topic started by: mat4 on May 15, 2008, 09:19:30 PM

Title: valve tappet clearence
Post by: mat4 on May 15, 2008, 09:19:30 PM

I have been told that through use the valve tappet gap gets smaller as the valve beds deeper into its seat, I always thought that with wear the clearence would increase not decrease, which is true, anyone know?

Title: Re: valve tappet clearence
Post by: SteveD CB500K0 on May 15, 2008, 09:32:51 PM

Wear causes the valve clearance to increase. So they rattle.

On DOHC bikes with shim/bucket arrangement, the opposite is true. As the shim wears the valve tightens. A nice quiet engine is not necessarily a good thing!  My Triumph Sprint ST came back from it's 24k service sounding all tappety (is there such a word?) as all 12 valves were tight.