Compression Ratios

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Hauula Pan
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Compression Ratios


Post by Hauula Pan »

Can someone tell me what the stock compression ratio was on a 1952 FL? My Panhead manual says 7:1 but I read elsewhere it was 8:1 and the supposedly low compression pistons I got a while back are 7.5:1 which would not be low compression if stock is 7:1 so I'm hoping someone can set me straight. Thanks.

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Re: Compression Ratios


Post by Bosheff »

Factory advertised comp ratio on a 52 FL was 7.2 : 1....bosheff

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Re: Compression Ratios


Post by RooDog »

You are not getting you numbers from a period correct Harley manual, are you? 8:1 should be be the FLH ratio from 1955 onward....

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