Author Topic: exhaust valve clearances  (Read 932 times)

Offline ferret

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exhaust valve clearances
« on: 21.05. 2012 12:32 »
My A10 recently started to leak oil from the rocker cover.  I fitted new gaskets but whilst re-assembling, I misaligned the  pushrods with rocker cups, and managed to bend an exhaust valve and snap the valve guide in the process.  Things were put back together with new valve and guide and new push rods (because the old ones had bent slightly).  Oil leak is sorted, but the rocker adjustment on the exhaust valves is now at it's limit with virtually no thread visable past the locknut.   Has anyone else out there had this,  or do I possibly have incorrect push rods.   I recollect that there was plenty of thread visible with the old push rods. 

Bike runs ok and I have been for a 30 mile ride on it.
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Offline fido

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Re: exhaust valve clearances
« Reply #1 on: 21.05. 2012 12:48 »
Perhaps you have A7  pushrods, did you compare lengths before fitting? I had a similar problem with my A7SS but that was because the tubular part of the pushrods had splayed at the ends slightly, making them shorter.
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Online bikerbob

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Re: exhaust valve clearances
« Reply #2 on: 21.05. 2012 15:19 »
HI there. Yes I have had this problem before but it was the inlet push rods that were the wrong length they allowed the adjusters to hit the rocker covers. I did contact the manufacturer at the time but even after sending them back with a correct one they would not admit that they were wrong. So I obtained correct ones from another supplier. This was about 12 years ago.
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Offline ferret

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Re: exhaust valve clearances
« Reply #3 on: 21.05. 2012 21:20 »
Thanks fido and bikerbob.  I agree, it must be wrong pushrod size.  I must admit I didn;t really compare them with the old ones.  The old pushrods appear to be made of a heavier material, the new ones being a lighter alloy.  I'll shop around for some more.   Cheers.
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Offline chicago

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Re: exhaust valve clearances
« Reply #4 on: 27.05. 2012 11:48 »
hi there, i dont know if its any help but my a7 longstroke is the same, i.e with the adjusters screwed right out. i think my pushrods might also be too long  ???? ????.
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alt: Share http://i438.photobucket.com/albums/qq110/chicargo/SDC17421.jpg[/img]
bit worrying as i did notice that the tappet adjusters dont sit flat on the top of the valve when screwed right out, might cause a lot of undue wear ?. all the best, chicago
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Online muskrat

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Re: exhaust valve clearances
« Reply #5 on: 27.05. 2012 20:51 »
 For the geometry to be right at 1/2 lift the tappet should be in line with the valve stem. So either a shorter push rod or thicker rockerbox or cylinder base gaskets would help.
Cheers
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Offline ferret

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Re: exhaust valve clearances
« Reply #6 on: 28.05. 2012 12:45 »
thanks Muskrat and Chicago, appreciate the advice.  Work in progress.
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