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Author Topic: ring gap for pistons  (Read 750 times)

Offline jakebass12

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ring gap for pistons
« on: August 04, 2012, 11:58:30 AM »
hello i found this link (http://www-cdr.stanford.edu/~petrie/bmw/R80ST/engines.html) about the ring gap and it also has some other stuff. i was wondering if the sizes are the right ones.
1981 bmw r65. 1981 kawasaki kz550

Offline nhmaf

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Re: ring gap for pistons
« Reply #1 on: August 04, 2012, 10:58:07 PM »
Quite alot of info there - though I have seen some of the same tables (I think that they were the same - at least they had the same font, spacing, etc.) on another website before.

I hadn't known that some of the ranges of ring end gaps were so wide - I seem to think that .0120" was the typical/ideal value, which would be toward the minimum end of the range in this chart.
« Last Edit: August 05, 2012, 11:39:24 AM by nhmaf »
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tvrla

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Re: ring gap for pistons
« Reply #2 on: August 05, 2012, 09:48:27 AM »
Installing new rings?

Seems like .010" is pretty standard. When I recently re-ringed the 850 R65 with the same pistons and only slight honing, I set the gaps to something like .007". I was a little concerned about the rings possibly seizing, but it all worked out fine.

I used this data and swear by it:

http://www.mototuneusa.com/break_in_secrets.htm