TRX450R Valve Adjustment HOW-TO

[trx450jason]

well i have it all figured out and back together and it runs and starts so much better than before.. i put in the Hot Cams 2 cam and the motor runs a little louder but ive heard thats normal. your writeup helped a lot

[ghott]

Thanks for the kind words...

And yes....

In my bike, both the Hot Cams Stage 2, and Stage 3 have ticked much louder than a stock cam. As long as your clearances are on, your golden.

[d3ktrix]

Found an error in the guild tonight while I was installing my 02 CRF cam.

Nothing major.

In step 7 it says:

"Set the engine to TOP DEAD CENTER (TDC) by completing the following tasks: Remove the Crankshaft Hole Cap (10mm allen wrench) on the bottom right side of the engine (near the transmission fluid check hole). Inside the crankshaft hole, use a 10mm allen wrench to rotate the crank manually to line up the timing marks on the sprocket and case (shown in the first picture below circled in GREEN)."

To turn the crank shaft, you need to use an 8MM allen wrench, not a 10MM.
10MM is correct for the cap still though.

Your guild was super helpful tho, thanks =)

[ghott]

Originally posted by d3ktrix
Found an error in the guild tonight while I was installing my 02 CRF cam.

Nothing major.

In step 7 it says:



To turn the crank shaft, you need to use an 8MM allen wrench, not a 10MM.
10MM is correct for the cap still though.

Your guild was super helpful tho, thanks =)

Thank you, I will change that ASAP!

[ghott]

Updated it today.

[redrider03]

Very nicely done!!! Looks good

[ghott]

Originally posted by redrider03
Very nicely done!!! Looks good

Thanks!

[wildheer]

Hello, i want to say that this is an excellent how to and very well done. I have a question about shims. I have an 06 450R and i will be installing the HRC soon but my questions are just assuming keeping everything stock. When it comes to adjusting the valves, are there no screw adjustments? The full adjusting is done through shim replacement only? How do the shims get out of adjustment? Is that just through the natural wearing of them? Assuming keeping the same CAM, how would you ever need to add a smaller shim if this is the case. It would seem the adjustment would always be adding the exact shim the bike came with or maybe slightly bigger to make up for another part wearing but how could you ever put a smaller one in? Also, i didnt see where you mention adjusting the decompressor clearance after the valve adjustment. I do understand this is done by an adjustment screw and the manual says to always do this after a valve adjustment or inspection. What is your take on this? Thanks again for such an informative how to.

[golfer2000]

Originally posted by trx450jason
i would say go for it.. its really easy to check the valves the only hard part is if you have to actually adjust them. but just to check them all you have to do is remove about 10 bolts

What do you do if you are just checking clearances? which 10 bolts?

[ghott]

Originally posted by wildheer
Hello, i want to say that this is an excellent how to and very well done. I have a question about shims. I have an 06 450R and i will be installing the HRC soon but my questions are just assuming keeping everything stock. When it comes to adjusting the valves, are there no screw adjustments? The full adjusting is done through shim replacement only? How do the shims get out of adjustment? Is that just through the natural wearing of them? Assuming keeping the same CAM, how would you ever need to add a smaller shim if this is the case. It would seem the adjustment would always be adding the exact shim the bike came with or maybe slightly bigger to make up for another part wearing but how could you ever put a smaller one in? Also, i didnt see where you mention adjusting the decompressor clearance after the valve adjustment. I do understand this is done by an adjustment screw and the manual says to always do this after a valve adjustment or inspection. What is your take on this? Thanks again for such an informative how to.

The valve seats will wear over time/use and require the shim adjustments...they are a normal wear and tear item. You can certainly minimize the amount you will have to adjust the valves by using high quality valves, seats, guides, and springs as well as using a cam which is easy on the valve train and doing routine oil changes and air filter cleanings.

The decompressor adjustment is something I didn't want to include in the how-to because I don't feel its all that necessary. Others may disagree with me, but I've never had to adjust mine. In addition to that, there are varying ways to check the decompressor arm adjustment to...whether it be with a compression gauge or a simple feeler gauge test. I believe there is also a big difference as to what year bikes like what kind of decompressor adjustment...the kickers vary from the electric starts. I really didn't want to get into all that. Just follow what your manual or engine builder recommends.

Originally posted by golfer2000
What do you do if you are just checking clearances? which 10 bolts?

4 bolts - front plastic to gas tank/frame
2 bolts - gas tank to frame
4 bolts - valve cover

VOILA!