Changing out valve shims

[forfiddy]

I have a 2009 rmz 450, I know i need to redo my shims considering it does not want to cold start. I've never done internal motor work on anything but this seems doable. I've found a few good youtube videos of a how to, i also have the manual for the bike.  Ill have a buddy with more experience by my side. The one confusing part was the math of how the guy knew which size shim to put in.  Here is the video that i thought was the most beneficial.  

 

 

I was hoping to hear from some who have done it before and know a few major details not to overlook. 

[hyperlitebitt]

Buy a digital caliper and feeler gauges that displays in mm readings to make the math easier. I have attached a link showing a valve adjustment on a ktm 350. It has a part that shows in good detail how to do the math. http://www.omraoffroad.com/forum/viewtopic.php?f=40&t=11399

[Rotaholic]

No real math needed, in the manual it tells you exactly which shim you need using their chart. Job done

[JFM43]

The biggest difference is that your bike has two cams. The honda has one.

This is a better video for you.

https://www.youtube.com/watch?v=VvKOc7kJASI

Edited November 3, 2015 by JFM43

[jimbopitts]

You need to actually check the clearance to find out if you need to re shim the valves

[forfiddy]

Thanks for all the help guys, and yes obviously I will check them before i changed them...

[BDubb106]

You say you need to "reshim". Has this bike been shimmed before? If so you need your head rebuilt. Shims are only a temporary fix. 

[forfiddy]

Not to my knowledge, its been a great running bike up until recently. I live in the rocky mountains right next to desert, So extreme differences in elevations, i have had to mess with my idle a little at times when in switching elevations.  According to my spark plug i was running lean, but the bike idled and ran great...