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Compression PSI on an '81R00

jupiteral

New member
Having a valve job done. Does anyone know how much compression P.S.I. an R100 is supposed to put out ? Thanx
 
A rule of thumb is one atmosphere above the compression ratio, converted to psi. For the '81 R100, the compression ratio was 8.2:1, so 9.2 times 14.7 is something like 135.
 
My 1980 R100RT already has the 8.2 pistons - they stayed thru 1984 for US bikes. unless, of course, your bike is Euro, or previously modified
 
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