Author Topic: Piston Ring question  (Read 842 times)

Offline renos-a10

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Piston Ring question
« on: 13.01. 2011 12:32 »
Hello guys.
I am thinking if the piston rings have a rotation? *conf*

Thanks
Renos
1954 BSA A10 Plunger
Cyprus

Offline LJ.

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Re: Piston Ring question
« Reply #1 on: 13.01. 2011 14:12 »
Hi Renos... I think when the piston rings are new and fitted to a rebored cylinder they must surely rotate to some extent until they find a place to rest and then bed in. When ever I have fitted rings they are always in a different place when cylinder is removed. I usually put the oil scraper ring join at the back of engine 6'o'clock, then middle one at 2'o'clock position and top ring at 10'o'clock. I would not think that the rings are rotation constantly, I maybe wrong though... Interesting question!
Ride Safely Lads! LJ.
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1940 BSA M20 500cc Girder/Rigid- (SOLD)
1947 BSA M21 600cc Girder/Rigid-Green
1949 BSA A7   500cc Girder/Plunger Star Twin-(SOLD)
1953 BSA B33  500cc Teles/Plunger-Maroon
1961 BSA A10  650cc Golden Flash-Blue
1961 BSA A10  650cc Golden Flash-Red

Offline A10Boy

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Re: Piston Ring question
« Reply #2 on: 13.01. 2011 15:57 »
If my memory serves me right, I was taught that when building an engine the top ring is positioned so that it's gap is farthest away from the exhaust vale. The other rings are spaced out equidistantly ? equally spaced. I never imagined that they would move much, but I suppose they must do a bit.
Regards

Andy

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Offline renos-a10

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Re: Piston Ring question
« Reply #3 on: 13.01. 2011 21:44 »
Thanks guys! apriciate for our help
1954 BSA A10 Plunger
Cyprus

Online BSA_54A10

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Re: Piston Ring question
« Reply #4 on: 14.01. 2011 12:10 »
Yep, they go round and round and round.
This is why strokers have pegs in the groves, to stop the gap fouling on the ports
Bike Beesa
Trevor