Lash me whip me, you know I need it

3 replies to this topic
  • Waxer

Posted February 07, 2006 - 06:15 PM


99 WR400, new head & valves. This is the first valve lash adj on the new head. I have R&R the shims & 4 of the 5 valves are within tolerance now(previously all were 2-3 hundreths of a MM tight. Now 1 of the intake valves is 2/100ths of a MM loose.

Yamaha intake specs= .15-.20MM
old lash=.127MM with the 191 shim
new lash=.22MM with the 185 shim

Old shim was a 191, new shim is a 185. Yamaha only sells increments by 5, i.e. 185, 190, 195 etc. I was previously using the 191 & it was slightly tight whereas now it is slightly loose. I could go to a 190 but how much difference there would be from the 191? I could also hand lap the 191 down w/ 600 grit but I only need 2/100ths of a MM. Any ideas about running the current 2/100ths of a MM loose or should I order the 190 shim or lap the 191?

Thanks for your support :thumbsup:

  • ncampion

Posted February 07, 2006 - 07:10 PM


Don't be obsessive about vlave lash. I didn't even know you could get shims in less than .005mm increments

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Waxer

Posted February 08, 2006 - 07:16 AM


In the past you were able to obtain shim's in increments by one, now Yamaha only sells increments by five.

  • SXP

Posted February 08, 2006 - 07:19 AM


If you can't dial the clearance in to spec then err on the loose side. You should be fine :thumbsup:


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.