Tight cam


2 replies to this topic
  • tr72

Posted May 29, 2014 - 08:41 AM

#1

I have a 2006 YZ450F and adjusted the valves. vales clearance is spot on BUT when I torque down the cap (10nm) on top of the cam the cam gets tight to the point that it wont move freely on the exhaust side. With no tension on the cam chain the intake side moves free, the exhaust side is tight unless I loosen the cam cover cap. 1/2 circlips are in the bearings, circlips slides into the groove in the cap and that should line up the cam in the head (journals) correct ?? It seems so simple, I don't see what I'm doing wrong. There are no marks or any issues with caps or the head, any ideas would be greatly appreciated.



Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted May 29, 2014 - 10:48 AM

#2

Assuming that the cap is seated squarely (no debris, burrs, other damage causing it to tilt) and that you have torqued it in the correct sequence to the correct values, it may actually be normal.  I've seen several of the four-stroke YZ's in all sizes that behaved like that, including the YZ250F I owned. 

 

Check the clearance in the cap using Plasti-Gage as shown in the manual.  If it shows to be OK, then run it.  Remember that the head heats quickly, and that will loosen the cam bores as it happens.



  • tr72

Posted May 29, 2014 - 05:29 PM

#3

I could understand if there was a little drag but this one doesn't budge at all, even when only torqued down to 3nm, intake side is smooth as silk. I'll keep playing and see what happens.







Related Content

Forums
Photo

yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies
Forums
Photo

James Stewart back on a YZ450F by YamaLink


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies
Forums
Photo

Is it worth it? (Cam and High compression piston) by macgi77


Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Wiki
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info


Articles
  • 0 replies
 
x

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.