HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
jbehunin

'07 YZ450F valves

4 posts in this topic

I was measuring the valves on my 2007 YZ450F this morning and saw that the exhaust valves were a bit out of spec. The intake valves were fine.

The exhaust valves, according to my manual are to be about .25, and mine were at .17.

I had a 170 pads in there, but what number pad should I get to put it back in spec? I have asked every mechanic I know, and they said to just toy with it and see what happens, but I dont want to tear apart the bike just to see what will work and what wont, plus those things are 6 bucks each!!!!

Thanks for any info you can share with me.

Share this post


Link to post
Share on other sites

Your valves are at .17mm, and the minimum is .20mm, so they are how far out of spec?

Then, if we need to increase the clearance, do we need a smaller, or larger shim?

Good. Now, since your current shims are 1.70mm, what size in .05mm increments will make the clearance fall within the correct specification of .20-.25mm?

Answers to come.

Share this post


Link to post
Share on other sites

> 1) The valves are .03mm out of spec.

> 2) Smaller. A smaller shim will reduce the assembled height of the valve stem/lifter and increase clearance.

> 3) 165. A 165 shim measures 1.65mm, .05mm smaller than the 170, increasing clearance by .05mm. Since the current clearance is .17, increasing it by .05 will make it .22mm. .22mm falls squarely between the specified minimum and maximum of .20-.25mm.

:worthy:

Share this post


Link to post
Share on other sites
> 1) The valves are .03mm out of spec.

> 2) Smaller. A smaller shim will reduce the assembled height of the valve stem/lifter and increase clearance.

> 3) 165. A 165 shim measures 1.65mm, .05mm smaller than the 170, increasing clearance by .05mm. Since the current clearance is .17, increasing it by .05 will make it .22mm. .22mm falls squarely between the specified minimum and maximum of .20-.25mm.

:worthy:

THANK YOU!!!!!!!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0