CRF250R valve shimming question

[bull413]

I checked the valve clearance on my 06 crf250r and both exhaust valves is at .007 and the intake is (left side) .005 and (right side) .000??? idk my feeler gague only went down to .002 and it would not slide in.

Is that ok for the exhaust? Do I need to just shim the right side on the intake? or does both need shimming?

[Charlie C]

You need to shim the exhaust to at least .008", but the next size smaller shim will work fine. You can re-shim your right intake valve between .004" and .006", but it's going to zero out in a very short amount on time. The valves need to be replaced and the seats will need cut. There's no 2 ways about it.

[i4bikes]

You need to shim the exhaust to at least .008", but the next size smaller shim will work fine. You can re-shim your right intake valve between .004" and .006", but it's going to zero out in a very short amount on time. The valves need to be replaced and the seats will need cut. There's no 2 ways about it.

I'm sad to say this guys dead on. You need to replace those valves. I can say without a doubt that intake valve will not hold adj. and if you try to run it to long that motor will blow up from a stuck or broken valve. Sorry, wish I had better news.

[bull413]

Any suggestions on what kind of valves to get without spending alot of money and would stainless be better? can I just replace the intake or do I need to replace all four? Thanks for the help. I kinda figured that was gonna be the answer when I seen that one at .000

[charliep]

I just replaced my sons intake valves on an 07 CRF250R. We race desert in CA. I shimmed the right intake a couple times, it only lasted one ride each time.

I replaced the intakes only, the exhaust valves looked good and I never had to shim. I bought the Kibblewhite intake kit, stainless steel. The seat had to be re-cut on the right intake.

[lv4snow]

I just replaced my sons intake valves on an 07 CRF250R. We race desert in CA. I shimmed the right intake a couple times, it only lasted one ride each time.

I replaced the intakes only, the exhaust valves looked good and I never had to shim. I bought the Kibblewhite intake kit, stainless steel. The seat had to be re-cut on the right intake.

+1 did the same thing about 2 years ago and valve clearances havent moved. i just saw an intake only kibblewhite kit on ebay for $161.

[bull413]

Ok if I just replace the intake do I need to put new springs on the exhaust valves also?

And what about the shims, do I use the ones that is already in there? or how do I know which ones to use?

[Charlie C]

Ok if I just replace the intake do I need to put new springs on the exhaust valves also?

And what about the shims, do I use the ones that is already in there? or how do I know which ones to use?

You really don't need to replace the exhaust springs, but it's wise at $8 each. It's pretty much cheap insurance. You probably will not be able to use the original shims. Being that the seats will be cut down, your going to need a thinner shim for the new valves. Which one exactly I couldn't tell you. It's trial and error at that point.

[TheBoonDocker]

You will be better off buying a HotCams shim kit. At $70, you can reshim and reshim without paying someone to do it at $80 bucks a shot. If you dont have a manual, I would highly reccomend one. P.S. dont drop the shim down into the crank.

[07crf250rider]

What are good valves to buy? i have a 2007 crf 250R and i heard a a knock from it but i knew that that was the decompression thing. Then i started hearing a rattle going on so i just shut it off immediately cause i didn't want it to drop a valve. So i took valve cover of changed oil cleaned the spark plug off really good and put everything back together and it quieted them down a lot. But i  really didnt want to drop a valve so i took the head off and there was a wear mark on the right intake side on the piston. Is that what i was hearing? and also can i just take the head to a dealership and they can re shim them or do they need the whole bike. is here a way to get around of adjusting the valves so many hours.

[Incredible78]

Go to big bore thumpers or Fastheads to get your head re done

[nzgsr]

Rattle sounds are more likely from the cam chain due to the tensioner failing. As the tensioner backs off it is possible for the piston to contact the valves. Either way something major is going wrong with your bike. Your probably looking at a valve job, piston kit, new cam chain & tensioner. Could also be some damage to the crankshaft if the piston was hitting the valves. Then your also looking at a crankshaft and bearings.

[07crf250rider]

I am just going to do a valve job cause cam chain is new and tensinor is but the vales are bad i am going to piut kibblewhite valves in it

[imbackmkay]

make sure you use the kibblewhite spring kit and get the seats cut and the guides are in spec

[07crf250rider]

will do thanks every one

[Anders Sarkinen]

Not me reading this as my bike is having the exact same issue?

[jsteele88]

07 crf 250r was starting up first and 2nd kick but past few weeks it takes quite a few  kicks and backfires when while kicking. when warmed up it also takes a lot of kick . just started doing not too long ago. should i try and shim or just get new valves or whats the best option ?

 

[Garage_Dog]

(You should start your own topic)

Check valve clearance.  

Check compression/leak down test.

Depending on how much you ride, how long you want to keep the bike and your type of riding... shimming might be fine or you may want to put in new valves.