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rd400 oil pump shimming

Started by BCRD, February 20, 2026, 03:39:47 PM

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BCRD

just to get this straight.. when setting oil pump stroke, more stroke means more oil?? factory specs are .0080-.01" i beleive. ive seen a rebuild spec card from ed toomey showing a rd400 pump set to .012" is that what i should set mine to?? im fine with a bit more oil

SoCal250

#1
Yes the factory spec is 0.20~0.25mm for minimum stroke. That 0.012" would be about 0.30mm.
More stroke = more oil output
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