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Valve clearances after rebuild

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Hi, I'm new to dirt bikes and this forum.

I recently bought an 05 kxf250 of a guy who buys and fixes bikes.

He said the bike was just after a top end rebuild etc and gave me the old piston which was replaced.

I checked the valve clearances and they are way out, exhaust valves had both 0.09mm clearance and the manual said it should be 0.17-0.22 The intake valves had 0.08mm and should be between 0.10- 0.15mm. I was wondering if the clearances change often after the rebuild and should I buy a shim kit at £60 or just get 4 shims. I don't mind spending the money if yous think that I will need to replace the shims pretty often ?

Sorry if I have posted this in the wrong place, if I have where is the proper place to post this sort if question.

Thanks

Edited by Gracey222

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Cheers mike, I've only been one the bike for about 2 hours total and not giving it to much thrashing, is there anything else you would do or check etc so far I have replaced:

Front and rear pads

Oil & filter

Air filter

Upper and lower rear shock bearings

Checked fork seals ( one is a starting to leak slightly)

Everything seems ok but is there anything really important to check when buying a used bike ?

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Cheers mike, I've only been one the bike for about 2 hours total and not giving it to much thrashing, is there anything else you would do or check etc so far I have replaced:

Front and rear pads

Oil & filter

Air filter

Upper and lower rear shock bearings

Checked fork seals ( one is a starting to leak slightly)

Everything seems ok but is there anything really important to check when buying a used bike ?

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Apologies I meant to say 0.17-0.22 and it measured 0.09 for exhaust and 0.08 for intake

 

Thanks for the clarification.  

 

My concern at this point is why are they all off by the exact same amount?  There are 4 measurements to take, one for each valve.  I am also concerned if they are tight after a top-end rebuild.  No reason on earth not to shim them at that point.  If they were shimmed to spec at the time of the rebuild, there are 3 possibilities.  First, the shim job may have been done wrong.  Second, your measurements could be wrong.  Third, worst case, the Ti valves are losing clearance quickly, which means you need new valves before you grenade your motor.  

 

In the third case, you could just re-shim and see if they hold, unless they are bottomed out, which you won't know until you take it apart.  If you do that, you have to revisit after a very short period of time to see if they tightened again.  Once these valves go, they go quick.  They are expensive to replace, but not as much as a whole new top end.  Please feel free to ask any more questions or clarify.  You want the bike right, and lots of people here are willing to help.  The more info the better.

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I was in tas Suzuki over here who knows the bike and said that when the man was ordering shims he wasn't 100% sure what size he needed and just ordered what he thought he needed. So I'd be inclined to think it was option 1.

Is there much stripping to be done when you were saying about the valves being bottomed out. What all would I need to take off and what am I looking for lol

Also because I've had the bike out ( even for a short period of time) will the valves being this tight have caused damaged ?

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I was in tas Suzuki over here who knows the bike and said that when the man was ordering shims he wasn't 100% sure what size he needed and just ordered what he thought he needed. So I'd be inclined to think it was option 1.

Is there much stripping to be done when you were saying about the valves being bottomed out. What all would I need to take off and what am I looking for lol

Also because I've had the bike out ( even for a short period of time) will the valves being this tight have caused damaged ?

 

If you reply by quoting, as I just did, you will get quicker responses, 'cause the person will know you are responding.  No damage from slightly tight valves.  First thing you do, buy a full service manual.  Then read it carefully for the work you are planning to do and follow every single step.  There is no substitute.  There are plenty of videos on shimming valves.  It is not difficult, but it does require steps to be done in order and with precision, specifically torque specs for the cam caps.  

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