Someone know the Compression(psi) of a stock 400ex [Archive]

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fourtrax400ex

11-01-2001, 05:23 AM

I would like to know the compression(psi) that a stock new 400ex should have, i know is a 9:1 ratio compression but how many psi?? someone know this???

thanks!

Glamis400ex

11-01-2001, 05:16 PM

between 100-128 psi as per Helm manual.

400exRacerX

11-01-2001, 07:00 PM

and i beleive it is 9.1:1 right?