Author Topic: Oval pistons and worn bores ??  (Read 1038 times)

Online bsa-bill

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Re: Oval pistons and worn bores ??
« Reply #15 on: 08.11. 2015 09:02 »
Quote
are we taking about ridge dodgers, designed to be fitted to a part worn bore to avoid hitting the wear ridge

so how does that work then if as has been said the step goes uppermsot as in TT pics (thanks TT)

I feel a Google coming on
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online Triton Thrasher

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Online bsa-bill

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Re: Oval pistons and worn bores ??
« Reply #17 on: 08.11. 2015 14:50 »
Cheers TT, I get it now, earlier pics show the step on the inside, depends which bit you call the step I suppose
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline v8ivor

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Re: Oval pistons and worn bores ??
« Reply #18 on: 08.11. 2015 15:16 »
Oh, the second photo makes sense to me, but the first diagram looked like it was doing the exact opposite to me. The rings that I took out were not like those and so I took a photo and I still can't attach it because it is telling me it's oversize,,, Grrrr ! (Jim Musky tried to help me post a photo but that don't work either )

Offline v8ivor

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Re: Oval pistons and worn bores ??
« Reply #19 on: 08.11. 2015 16:13 »
The old rings

Online bsa-bill

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Re: Oval pistons and worn bores ??
« Reply #20 on: 08.11. 2015 17:31 »
some ring info here http://www.andover-norton.co.uk/Norton%20GPM%20Gandini%20Piston%20Rings-%20fitting%20instructions.pdf

and this pic maybe suggest your rings are either just worn or wrong and upside down
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online Triton Thrasher

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Re: Oval pistons and worn bores ??
« Reply #21 on: 08.11. 2015 20:18 »
The old rings

Can you do one with the end in focus?

Offline v8ivor

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Re: Oval pistons and worn bores ??
« Reply #22 on: 08.11. 2015 23:09 »
Sorry TT, I had a hell of a job to post any photo at all. The rings are not like anything on your post Bill and because I can't think of any reason for a lip facing up or down + the lip on the outer edge is the same size as the groove, I'm thinking it's down to wear.