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CRF 80 - piston ring end gap

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Can anyone verify the end gap on the piston rings for a 2004 CRF80?

My manual shows "1998-1999" XR 80, then shows "2000 and later" XR/CRF 100 so I want to be sure before I put it back together.

For the 1998-1999 XR 80 it shows:

Top and second ring is 0.006 to 0.018

Oil rings are 0.012 to 0.035

For the 2000 and later XR/CRF100 it shows:

Top and second ring is 0.002 to 0.008

Oil rings are 0.008 to 0.027

Which measurements should I go with?

Also, do you soak the rings in oil or anything before installation?

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Rule of thumb.....

Piston diameter in MM................................Min. ring end gap

44 to 50____________________________.004inch

50.25 to 68__________________________.007inch

68.10 to 79.35_______________________.010inch

79.35 to 102_________________________.013inch

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Also rule of thumb, but...

http://www.wiseco.com/PDFs/Manuals/RingEndGap.pdf

Minimum gap

Top ring 0.007"

2nd ring 0.009"

Yes, oil your rings prior to installation; soaking them has no effect that I'm aware of (I've been wrong MANY times before). Also ensure a good coating of oil on all 'contact parts' of the piston; wrist pin, oil lands and ports etc. Take care to ensure none of your ring gaps overlap or are centered over the piston pin area.

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