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Just checked my valves, intakes are .0035 left and .0025 right.  exhaust were both .008.  

.005 +/- .001 is spec for intake and .011 is spec for exhaust.

Need to pull the head off (tomorrow) and see what size shims they were using, hopefully stock.  if so, I can shim it out and get a bit more time on the head.

I'd still like to know whats down the road ahead though.  Eventually, the valve job is coming.  If I order a the kibblewhite rebuild kit, what else is there to do?  re-cut the seats and...?  The rest I can do at home?

Anyone have any idea what size and angle the valves are? (I have a cutter kit for my VW heads, and wondering if I can cut them myself).

Advise is welcomed.

 

Cheers,

Mike

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Early 250X's are somewhat notorious for going through stock valves quickly.  The solution for many is SS valves (often Kibblewhite).  You'll need new springs and the full kit.  I believe the stock exhaust valves are steel. 

For professional help: AS Racing is a "guru" for rebuilding Honda X heads. 

Some 450X guys also throw a 3 ring (oil scrapper) piston from a 450 Honda Quad into their bikes to reduce oil consumption - not sure if 250X guys do the same.  If you have good compression / leakdown this may not be needed currently.  Your call there.

 

 

 

 

I have some Neway valve seat cutters for sale if you're up to the task.  I am certainly not and personally would send the head in for professional rebuild (hence the valveseat cutter sale)

 

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We ran into this issue on my son's 250X.  Got two adjustments before there were no more, they only make shims so small and the ones in there aren't far from the bottom of the line.  If I remember correctly, I sent the head in somewhere for stainless valves and possibly different springs due to the weight difference....I can't remember.  Supposedly it drops a bit of power but it wasn't noticeable and I like the reliability. 

 

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Unless the valve seals are beat to heck you can usually get by by lapping your kibblewhites in with a lapping compound.  No need to recut the seafs unless they are trashed.

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Took the head off today,  Documenting this here in case I lose my spreadsheet.  Intake: Left 1.7, Right 1.8  Exhaust: Left 2.35, Right 2.30

Now both intakes are .005 and exhaust a slightly tight .011  Good enough!!

 

Did some more research last night, Buying cutters is super expensive and not worth it for a home mechanic only working on his own stuff.  To purchase the K/W SS valve kit (200.00) + pay someone to cut valve seats (~120)  + shipping and whatever gaskets etc are needed hardly seems worth it when plenty of people are selling complete rebuilt heads for under 500.00  They must have it down to a science!.

I guess I'll put 20-30 hours and check the valves again. If they tighten up, then I'll debate the new cylinder head.   for now, there is still plenty of adjustment to go.

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