Author Topic: piston ring gap  (Read 1612 times)

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shakeyCZ

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piston ring gap
« on: November 04, 2011, 12:50:41 pm »
quick one putting in a new piston but the ring gap is not .05mm its .5mm i have not touched the new rings ( no sanding down yet) would this creat any problems would this be fine as the old piston rings gap was 1.0mm, just not quite sure how far the gap can be before i will have to go the next ring up or rebore to suit another new piston and rings, i was hoping to get away with using this free piston  and not having to buy a new one?

Offline Freakshow

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Re: piston ring gap
« Reply #1 on: November 04, 2011, 01:16:12 pm »
 half a mill sounds fine.  if it was fine on 1 mil, you in front  !
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Offline pancho

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Re: piston ring gap
« Reply #2 on: November 04, 2011, 04:28:32 pm »
 In the dark ages [when I was at tech] the standard set up was 3to4 thou.per inch of diameter. Air cooled on the high side.
cheers
« Last Edit: November 04, 2011, 04:30:27 pm by pancho »
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Offline oldyzman

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Re: piston ring gap
« Reply #3 on: November 04, 2011, 04:57:08 pm »
Like pancho said, so a 250 would be approx 12 thou or a bit more, i have had the same prob before on wiseco, but i noticed that wosner allways have had to be adjusted. so 1/2mm being 20 thou should be ok, make sure you put ya finger through the inlet port to help the rings get past as you slip the cylinder on- thats if its a two stroke.
Brett
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Offline pancho

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Re: piston ring gap
« Reply #4 on: November 04, 2011, 05:22:59 pm »
 Dont bite the end off your finger!
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shakeyCZ

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Re: piston ring gap
« Reply #5 on: November 05, 2011, 09:46:10 pm »
Thanks all,  i thought it would ok time to put her in