2003 WR450 Valve Inspection 3,000 Miles

9 replies to this topic
  • DRZBigB

Posted March 19, 2005 - 02:55 PM


I just helped my Brother check the valves on his 2003 WR450F...

I got these specs from a post on here - Are they correct?
Intake: .004" - .006"
Exhaust: .008" - .010"

Intake 1: .004 Exactly
Intake 2: .0035 (In Between .003 & .004)
Intake 3: .0035 (In Between .003 & .004)
Exhaust 1: .008 Exactly
Exhaust 2: .008 Exactly

SO - Do I need to reshim Intake 2 & Intake 3???

Is is CRUCIAL or is it OKAY?


  • RNS

Posted March 19, 2005 - 07:00 PM


Its Crucial to keep the valves in spec.


  • vmxr

Posted March 19, 2005 - 09:31 PM


I would reshim if it were mine.

  • Indy_WR450

Posted March 19, 2005 - 11:08 PM


Yes do them all to the high side or even .001" over the max clearance. :)

  • DRZBigB

Posted March 20, 2005 - 12:22 PM


Thanks - I'll tell my brother we need to reshim - are you SURE .001" OVER the specs, or just .006 and .010

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Indy_WR450

Posted March 21, 2005 - 05:35 AM


Dont go over unless you cant shim it close to the upper tolerance. :)

  • DRZBigB

Posted March 21, 2005 - 01:19 PM


We discussed it, and we are going to shim ALL the valves to the MIDDLE of the specs..

Intake: .005
Exhaust .009

I don't forsee them tightening up any more, and if they do, I'll just reshim it to the middle again in a year or so...

Sound Right?

  • Oasis_Flame

Posted March 21, 2005 - 01:24 PM


I went to the high side when I first did my valves and noticed lifter tap when the motor was up to temp. I now have them at .006 on intake and .008 on exhaust with no noise. :)

  • DRZBigB

Posted March 22, 2005 - 08:19 AM


Why would you put the intake at MAX spec, and Exhaust at MIN - is there ANY advantage, or just the "Tap,Tap,Tap"

  • vmxr

Posted March 22, 2005 - 11:59 AM


In the Jan 05 issue of Dirt Bike Magazine pg. 51, there is a description of the set-up on the Glenn Helen 24-hour winning YZ450 of Ty Davis. It mentions that the valve clearances are "set a thousandth looser than normal". I assume this is done for reliability. I have no idea what "normal" means in this context. But FWIW, I always set mine to max specified clearance and have had good results over more than 5000 miles on my 03 Wr450.

That said, I think if you check your valves regularly, and run the clearances in the middle of the spec there should be no problems.


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.