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
Strattos

250/426 valve shims

8 posts in this topic

I've just pulled my 02 WR426 down following a gearbox failure and am going to adjust the valves while the motor's out.

Can I use the shims from a WR250 in my 426?

Also, two of of the inlet measurements are right on the minimum at 0.1mm, but one is 0.12mm

According to the manual, shims come in .05 increments.

Now this is not a problem in relation to the first two valves, but if I go up one shim size on the 0.12mm clearance, that will take me to 0.17.

The book gives between 0.1 and 0.15 as the recommended range. Do I leave the third valve or change it to 0.17?

Share this post


Link to post
Share on other sites

hi,

#

yes look at the shim kit`s offered by hotcams`, i`ve just ordered both cams - the 400/426/450 use 9mm shim`s and the little bro`s use the 7mm shimmy`s

i think - ooh- not done that in a while!!

Share this post


Link to post
Share on other sites

Most of the original shims in your 426 are not in .05 increments. You should be able to switch most of them around to achieve close to middle of setting range on all 5 valves. If your third valve already has a .05 increment shim, leave it at .12 mm. (.10 -15 mm int./.20 -.25 mm exh.)

Share this post


Link to post
Share on other sites

If you want shims in 0.01mm increments go to a Honda dealer and order shims for the CRF450. They are also cheaper than the Yamaha shims.

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