Valve Shim Calculator and Log

I put together an Excel spreadsheet that calculates the required valve shims for a 4- or 5-Valve motor. Is there anyone who is planning to check their valves in the near future who would be willing to test it out and provide me with some feedback?

If so, please PM me with your email address and I'll send you a copy.:thumbsup:

Isn't that the same thing that's in the factory shop manual? :thumbsup:

Not exactly. The manual is a simple chart.

Not exactly. The manual is a simple chart.

the chart worked good for me. what else does your spread sheet do?

the chart worked good for me. what else does your spread sheet do?

It allows you to use shims with steps other than the Yamaha .05mm step shims, (i.e. the Honda .025mm step shims), provides part numbers for the correct shims from Yamaha, Honda or Hot Cams, and provides a log of all shim checks/changes.

My bike isn't due for a check and adjust but i'm always interested in a cheat sheet :thumbsup: maybe give it to the mod to add the the sticky :thumbsup:

My bike isn't due for a check and adjust but i'm always interested in a cheat sheet :thumbsup: maybe give it to the mod to add the the sticky :thumbsup:

I want to make sure that it gets thoroughly tested before being posted.

Where'd you get the specs for your spreadsheet? The manual says .005 for intake and .011 for exhaust

Where'd you get the specs for your spreadsheet? The manual says .005 for intake and .011 for exhaust

From the manual, in millimeters (since all of the shims are measured and marked in millimeters):

Valve Clearance (Cold)

IN .10 to .15 mm (.0039 to .0059 in)

EX .20 to .25 mm (.0079 to .0098 in)

LOL, sorry man, I actually wasn't even looking at your spreadsheet. I've been looking at a few different ones to compare results and got confused about which was whose. One had some numbers that didn't make sense to me, but it wasn't yours.:eek:

Excuse me for my ignorance, but Honda shims fit our yamahas? What models of Hondas?

Excuse me for my ignorance, but Honda shims fit our yamahas? What models of Hondas?

CRF-450R/X's are also 9.48mm diameter shims and CRF-250R/X's are 7.48mm diameter shims.

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