first valve adjustment


5 replies to this topic
  • focker811

Posted February 14, 2010 - 05:02 PM

#1

I am doing my first valve adjustment... its way late but i have been too scared to do it. I have read almost every thread on here about this and thanks guys you all really helped.

I just want to run this by you guys and make sure im doing the adjustments correctly.

my intake measured out at .007 for the outside and .006 for the middle, my shims measured out to be .070 for the outsides and .0715 for the middle.

if i did my math right I should replace the shims with a .072 or a 1.85mm shim.


my ex. measured out to be .0065 both sides with a .072 shim.

if my math is correct on this I should replace the shims with a .070 or a 1.80mm shim.

the tolerance in the book is calling out .0039-.0059 for the intake and .0079-.0098 for the ex.

Am I on the right track?



Another question is should I pull the head? The bike has at least 200hrs on it, with regular oil changes. up until the last trip it started fine, it was not until this weekend it started acting up. What should I do.

Thanks again for all the help:ride:

  • l_campionero

Posted February 14, 2010 - 05:28 PM

#2

If the cam chain is not kinky, don't take the head off.

  • grayracer513

Posted February 14, 2010 - 08:28 PM

#3

my intake measured out at .007 for the outside and .006 for the middle, ...

This in itself is very odd, and you should re-measure, or try to find out how it came to be. Clearance should decrease, not increase.

Another question is should I pull the head?

Assuming your measurements of the exhaust valves were accurate, you should keep your eye on the clearance for the next several hours, checking to see if the clearance remains as you set it, or continues to close up. The latter is an indication that the valves need replacement.

If the cam chain is not kinky, don't take the head off.

I'd like to hear the logic behind that one....

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • focker811

Posted February 14, 2010 - 10:47 PM

#4

i was thrown off by the decrease too... I will measure a fourth time tomorrow.

  • focker811

Posted February 18, 2010 - 11:48 AM

#5

I guess i miss measured the exhaust was in spec... time to button up the top and move on to the clutch! thanks guys

  • grayracer513

Posted February 18, 2010 - 12:04 PM

#6

I guess i miss measured the exhaust was in spec... time to button up the top and move on to the clutch! thanks guys


The specs you gave in the first place for the exhaust were in spec. It was the intakes that were fishy. They should have been in spec or smaller, but you listed them as larger. Then you said you were thrown off buy the decrease when there was no decrease.

Sorry, but I'm having a little trouble tracking you here.





Related Content

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
Forums
Photo

Megabomb Fitment by 288yz450


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply
Forums
Photo
Motocross

Thinking about Yamaha 250... by Arctic Pride


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 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
 
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.