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Exaust valves zero clearance

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If the valves are at zero do I see what shim is in there and reduce it by what the clearance should be?

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yeah the exhausts are solid... but the TI intakes on the stock seat are known to be pure garbage as far as im concerned. id bet money hes having problems with his intakes.

 

but yes, go .15mm SMALLER on your shims and go from there, that should get you damn close.

 

then take it on a solid ride, and check again.  you may need to adjust.

 

if theyre zeroed out, its pretty much time for a rebuild.  those valves are done my friend!  they will probably need to be re shimmed every 3-5 rides until you find you cant get a shim small enough. then shes really pooched at that point.

 

fastheads will rebuild your whole head for 399$.  springs, seats cut, everything. 

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Yes I'm at zero and my intake is .021,way off.just got bike and getting it dialed in but I'm new with motorcycles.is this going to need new valves and head?I don't want to put allot of money in the bike.

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Ok so I shim them to get the right clearance then ride and then check them and if there at zero again get head revalved?i checked fast heads and it looked more than you quoted.

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ok im confused.  you say youre at 0.00 then say youre at .021??   are you talking exhaust clearances here?

 

shim them and see how everything settles.  

 

I would shim them, start the bike for 3 mins in the shop, give it a few blips of the throttle, and re check them to make sure they havnt closed up again a hair.  it might need to possibly get adjusted once more after the initial -.15mm smaller, or it might be good and you can squeeze a few rides out of her.

 

once they start going out, it happens quicker and quicker every time.  first time youll get 20 more rides, then 10, then 5.

 

399$, maybe closer to 500 if you choose exhaust guides (I would) and get them to shim it for you too:  http://fastheads.biz/product/crf-enduranceservicepackage/

 

these things aint cheap. welcome to the crf/4 stroke dirtbike world!  if taken care of, and done right, they definitely do last a long time though.

 

hate to be the bearer of bad news but if your clearances are actually 0.00 then there aint much life left.

 

you positive youre doing it right?

Edited by coryf89

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you can find a shim calculator online to get you pretty close

fastheads is more like $540 when all is said and done

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buy an inlet valve and spring kit.get the valve seats cut and away you go..id be tearing the topend down now!

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Shim calculator?!?!?! What's wrong with good ol math and common sense??

this is the US, maybe you have better schools in Canada.  

Measure twice cut once....use shim calculator and be done! 

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