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Author Topic: Cylinder base gasket  (Read 1010 times)

Offline Drew Back

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Cylinder base gasket
« on: 20.05. 2015 13:46 »
I am ready to put my cylinder on and am using spacer plate because I have .40 over pistons question is do I need 2 gaskets??I only have 1 can I make the other out of cork??Do I really need the spacer plate??Otherwise its another 2 week wait from the UK.
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Offline duTch

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Re: Cylinder base gasket
« Reply #1 on: 20.05. 2015 14:40 »

 ?? not quite sure why you'd even need one spacer plate simply because of being .040 over...?
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Online bsa-bill

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Re: Cylinder base gasket
« Reply #2 on: 20.05. 2015 15:12 »
yes agree with duTch as long  we're talking +.040 diameter.
and don't think cork is a good idea for a gasket between crankcase and barrel, being as that is subject to compression forces
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Offline muskrat

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Re: Cylinder base gasket
« Reply #3 on: 20.05. 2015 21:15 »
G'day Drew.
Depends on the dome of the pistons (comp ratio). A 0.040" overbore will only increase the compression by about 5% so take a 7:1 up to a 7.35:1 and not worth worrying about.
Cheers
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Offline Drew Back

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Re: Cylinder base gasket
« Reply #4 on: 21.05. 2015 02:16 »
Very cool thats good to know I could swear someone said I needed the spacer plate anyway at least im one step closer..Thank You
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Offline Rocket Racer

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Re: Cylinder base gasket
« Reply #5 on: 24.05. 2015 01:24 »
If you're running on pool  petrol (72 octane) in some form of time warp back to the UK in 1955 then probably a good idea to fit it. 
Alternatively if you have compression over 10:1 otherwise I'd leave it out.
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