Author Topic: Re-ringing pistons of .040 with .060 over Hepolite rings  (Read 650 times)

Offline Rgs-Bill

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Hey you fellas, anyone who has tried this or has knowledge of some one who has, or just an engineering opinion of pro's or con's  of doing this.  Thanks in advance.
   Years ago a fella said he always used the next size up oversized rings, ex:  .040 over bore job with .040 over pistons, but use .060 over rings with the proper end gaps fitted.  Does any one out there have first hand info on such, or any opinion welcomed, from engineers or guys who have tried this, or racers, any one who could add to yes or no's on the   feasability of this method of fitting new rings only,  to .040 over pistons  ????

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1962 RGS
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Online muskrat

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 G'day Bill, the general rule is no. The rings are made to fit the bore (round peg in round hole). To do what has been suggested to you would be like an egg (in shell) in an egg ring. So the ring would exert more pressure on the bore in sections and less in others.
 But in saying that I have done it and they lasted OK. Just don't tell anyone. *conf*
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Offline kommando

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In a modern engine machined to tight tolerances it does not work, in an old engine where the bore is honed rough the rings wear so much as they bed in it makes no difference.

Have also done it too with no ill effects.
No BSA twins just unit singles