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Need advice, 05 CRF 450R valve clearance is .178 mm(very close) & .20 on the intake side, exhaust is .22mm on both valves. Plan on ordereing shim kit, but would like to ride this weekend practice moto track. am I to close to risk putting a few fairly easy hours on it. The bike only has around 20 hours on it total. Dont get to ride to often lattely & got to go when I get a chance. Bike starts & runs great, although I did foul a plug last time I rode it. Jetted for around 6,000' but was riding at around 9,000 ft altitude.

travis young wrote:Need advice, 05 CRF 450R valve clearance is .178 mm(very close) & .20 on the intake side, exhaust is .22mm on both valves. Plan on ordereing shim kit, but would like to ride this weekend practice moto track. am I to close to risk putting a few fairly easy hours on it. The bike only has around 20 hours on it total. Dont get to ride to often lattely & got to go when I get a chance. Bike starts & runs great, although I did foul a plug last time I rode it. Jetted for around 6,000' but was riding at around 9,000 ft altitude.

You need to recheck your timing. Those numbers don't sound correct.

One intake at .007 one at .008 and the exhausts at .009???

Sounds funky.

Bike starts & runs great,

What you wrote there means you aren't at TDC when checking the clearances ,because a bike that

Bike starts & runs great,

won't have clearances like that.
Most likely you did something like this, it's easy to do :
http://i86.photobucket.com/albums/k98/r ... -Marks.jpg
Doug

First time doing this, thanks for advice. Rechecked and intake is right at .007 but exhaust is .009 (tight.). I really want to ride.

I would absoutely go and ride bud.
Check this out and relax, you're letting the hysteria get to you .
First-Your intakes are fine and in spec, it wouldn't be a good idea to try and shim an intake valve from .007 to .006. It's in spec and the bike runs fine. Make double darn sure that you are at TDC before you start shimming things.
Is there a little freeplay/'slop' on the exhaust rockers when you firmly grab and shake them whle the motors at TDC ? There should be.
Does your bike have any false timing marks like the bike in that photo shows ?
I'd just be real leery of shimming those exhaust valves unless there was a problem of how the bike ran. When these bikes need a valve job they become hard to start,and it's the intakes that go first.
I'd go back and triple check,and see if those exhaust rockers will move or not. Doug

your awsome Doug, Thanks. Their is a little play in the rocker arm so I feel that im good to go. Ill keep watch on that clearance, & appreciate the education. Hope the moto is good in your area & thanks again. TY Colorado

You're welcome, go have a great time.
The weather is finally starting to turn,and I can't wait. Doug