[gthpprteam]

Has anyone noticed that the shim calculation method in the Honda service manual and owner manual winds up giving you the wrong
shim size needed when you follow it to completion. The CRFS online calculator is spot on when you put the values in.
I have searched this topic here and had not found any previous discussion about it.
If you use the Honda manual formula you will end up with valves that are still a little tighter than spec. I am just wondering what is missing in their calculation method and why in the hell would they publish that?

[crfsonly]

I don't think I have ever used the Honda manual for shim calculations. Pleased to hear you are using our calculator and getting the results you would expect.

As for valve clearances, the primary purpose of valve clearance is to allow the valves to close when they have expanded at operating temperatures. Too tight and they will stay open when they should be closed releasing precious compression. Too loose and they won't open soon enough and will close sooner reducing the time they are open. The Honda specifications is a good general guideline and what we recommend. However, they can be shimmed a bit tighter to increase the duration while still having enough clearance to close completely when they should be closed. However, doing so will require more attention to any clearance tightening. For this reason we recommend the standard Honda clearance.

Ken