Jump to content
Sign in to follow this  

valve shims/fork seals?

Recommended Posts

first off, my right fork seems to be leaving behind oil on the shaft. these are not stock seals, i replaced them and they dont have many hours on them. i know people on here have talked about some kind of film that i can use to get the dirt out with, but i cant remember the name of it, anyone know what i am talking about?

and is ok to run different size shims on the exaust valves. it seems to me that if i ran different size shims on the exaust valves it would put a lot of stress on the rocker arm, on the side with the bigger shim. on the intakes i couldent see a problem tho

Share this post


Link to post
Share on other sites
first off, my right fork seems to be leaving behind oil on the shaft. these are not stock seals, i replaced them and they dont have many hours on them. i know people on here have talked about some kind of film that i can use to get the dirt out with, but i cant remember the name of it, anyone know what i am talking about?

First release all the pressure out of the forks by removing the bleeder screw. Pull the wiper down and use a tear off or if you're carefull, use a thin feeler gauge to get between the seal and the fork tube. The seals are not that delicate so you're not going to ruin it. Use some wd-40 and take that skinny red tube and slide it between the fork tube and the feeler gauge. Remove the feeler gauge and use the red tube to go all the way around the fork tube. You will lose some of the fork oil, but not a lot. Just spray little shots of wd-40 to flush out the dirt. Most of the time, the fork oil that leaks out flushed the dirt out of the seal. I rarely find bad seals, just dirt in them unless the fork tube is nicked.

and is ok to run different size shims on the exaust valves. it seems to me that if i ran different size shims on the exaust valves it would put a lot of stress on the rocker arm, on the side with the bigger shim. on the intakes i couldent see a problem tho

Be more specific, you lost me on that last part about the shims.

Share this post


Link to post
Share on other sites

thanks, gonna do that some time this week.

what i mean on the shims is can i have 2 different size shims on the right and left exaust valves? For example: a .008 size shim in the right exaust valve and a .011 size shim in the left exaust valve?....same with the intake valves?

Share this post


Link to post
Share on other sites

oww and one more question! how can i fit a 14 tooth front sprocket on my 06. I have a 51 tooth rear, would putting in a extra master link work to get the chain to fit? and will a 14 tooth even fit on there, pretty sure it will with the gaurd removed, correct me if i am wrong

Share this post


Link to post
Share on other sites

for the seals, try the film trick, but I have had bad luck with aftermarket fork seals (I used MSR). My 250X is very particular about OEM fork seals. I have never had a problem with OEM fork seals, where aftermarket are kind of hit and miss.

On the shims..... no problem. As long as the valve clearances are roughly the same, the load will be equal across the rocker arm. On top of that, the rocker is plenty strong enough to open one valve even if the other spring is completely gone. Remember, the shims just set the clearance. Once that clearance is taken up by the exhaust starting to open, the spring force on each side of the rocker arm is exactly the same.

Share this post


Link to post
Share on other sites
thanks, gonna do that some time this week.

what i mean on the shims is can i have 2 different size shims on the right and left exaust valves? For example: a .008 size shim in the right exaust valve and a .011 size shim in the left exaust valve?....same with the intake valves?

Sorry, I wasn't sure exactly what you meant, but it looks like you got the answer of yes. I'm kind of surprised that they were not different sizes to begin with.

Share this post


Link to post
Share on other sites
for the seals, try the film trick, but I have had bad luck with aftermarket fork seals (I used MSR). My 250X is very particular about OEM fork seals. I have never had a problem with OEM fork seals, where aftermarket are kind of hit and miss.

On the shims..... no problem. As long as the valve clearances are roughly the same, the load will be equal across the rocker arm. On top of that, the rocker is plenty strong enough to open one valve even if the other spring is completely gone. Remember, the shims just set the clearance. Once that clearance is taken up by the exhaust starting to open, the spring force on each side of the rocker arm is exactly the same.

thanks, just what i was looking for.

Sorry, I wasn't sure exactly what you meant, but it looks like you got the answer of yes. I'm kind of surprised that they were not different sizes to begin with.

ha no prob you help me enoughf, but will i be able to run that 14 tooth sprocket with and extra master link in the chain?

Share this post


Link to post
Share on other sites
thanks, just what i was looking for.

ha no prob you help me enoughf, but will i be able to run that 14 tooth sprocket with and extra master link in the chain?

I'm not so sure, I never ran a 14t on the front of the 250. On the 09 450 we run a 14/52 for outdoors and the chain is way too long for the 13/50 we run indoors. We have 2 chains. What to you plan to use a 14t up front with? Do you plan on changing the rear?

Share this post


Link to post
Share on other sites
I'm not so sure, I never ran a 14t on the front of the 250. On the 09 450 we run a 14/52 for outdoors and the chain is way too long for the 13/50 we run indoors. We have 2 chains. What to you plan to use a 14t up front with? Do you plan on changing the rear?

the rear is a 51 tooth, i dont ever plan on changing the rear till it is shot, and its a supersprox so thats gonna be a while. if i have to get a second chain thats no big deal but if i can get buy with just another master link that would be better

Share this post


Link to post
Share on other sites
the rear is a 51 tooth, i dont ever plan on changing the rear till it is shot, and its a supersprox so thats gonna be a while. if i have to get a second chain thats no big deal but if i can get buy with just another master link that would be better

You know you're going to lose your bottom end. Adding another masterlink isn't going to help. You need another center link to add for another masterlink. Follow me? How far back in the rear wheel? Can you move it forward? The sprocket isn't that much bigger.

Share this post


Link to post
Share on other sites
You know you're going to lose your bottom end. Adding another masterlink isn't going to help. You need another center link to add for another masterlink. Follow me? How far back in the rear wheel? Can you move it forward? The sprocket isn't that much bigger.

dont care if i lose boddom end, i would only be using that gearing when going on high speed runs in the ditches/ section lines, almost never leaving 5th gear. ya your right i would need another center link too, mabey i will just get another chain just make it simple on myslef lol. unfortunatly the rear wheel is adjusted all the way forward, but it wouldent matter if i just got a second chain

Share this post


Link to post
Share on other sites

I am checking the valve clearance on my 2010 CRF250. As they wear ; do the clearances become tighter , or looser ?

thanks

Share this post


Link to post
Share on other sites
I am checking the valve clearance on my 2010 CRF250. As they wear ; do the clearances become tighter , or looser ?

thanks

Tighter, but hopefully, they didn't move.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×