wr450f 06 model valve clearance question


2 replies to this topic
  • tttalker

Posted August 15, 2007 - 11:51 PM

#1

wr450f 06 model
650 km's
not ridden overly hard
grey wire
air box
fmf pipe
Never been check for valve clearance
Serviced every 250km (oil, filter)


Hello guys,
I have recently had a mechanic check my valve clearances and these where the results.

Exhaust Valves (pad changed from/to)
1. 170 to 160 (Measured clearance -0.00~0.04)
2. 169 to 160 (Measured clearance -0.00~0.04)

Intake Valves:
1.180 to 175 (Measured clearance -0.15~0.19)
2.185 to 180 (Measured clearance -0.15~0.19)
3.180 to 172 (Measured clearance -0.10~0.14)

My questions:
1.Since the valves have never been done ... is there any reason why the original pad thickness was not 175 as specified in the manual.
2. What could of caused such a small clearance across the board?
3. Is it possible to get pad increments other than by 5 ... eg. 172 and 169?
4. How can i check to see if this mechanic is not talking bulldust?

Also .. he beleives that the needle in the carby is the restricted type and needs to be replaced ..... how can i confirm this? and is there a big performance difference if this is done given the other mods
Cheers.

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

Posted August 16, 2007 - 08:00 AM

#2

wr450f 06 model
650 km's
not ridden overly hard
grey wire
air box
fmf pipe
Never been check for valve clearance
Serviced every 250km (oil, filter)


Hello guys,
I have recently had a mechanic check my valve clearances and these where the results.

Exhaust Valves (pad changed from/to)
1. 170 to 160 (Measured clearance -0.00~0.04)
2. 169 to 160 (Measured clearance -0.00~0.04)

Intake Valves:
1.180 to 175 (Measured clearance -0.15~0.19)
2.185 to 180 (Measured clearance -0.15~0.19)
3.180 to 172 (Measured clearance -0.10~0.14)

My questions:
1.Since the valves have never been done ... is there any reason why the original pad thickness was not 175 as specified in the manual.
2. What could of caused such a small clearance across the board?
3. Is it possible to get pad increments other than by 5 ... eg. 172 and 169?
4. How can i check to see if this mechanic is not talking bulldust?

Also .. he beleives that the needle in the carby is the restricted type and needs to be replaced ..... how can i confirm this? and is there a big performance difference if this is done given the other mods
Cheers.


1.The 175 in the manual is just an example. They will all be different. 2.Valves will tighten up as they seat with some break in time. 3.You can buy Honda shims for the crf450 in 2.5 increments. 4.Do the job yourself. If your needle is the stock non adjustable one then yes you could see an improvement with better jetting. :thumbsup:

  • WR_Dave

Posted August 16, 2007 - 05:39 PM

#3

You've got a pretty good answer from trailordune, see if there are any of the great Aussie contributors in your neck of the "outback" and see if they wouldn't mind helping you out a bit. :cheers: WR Dave.




 
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.