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phragle
04-24-2010, 03:12 AM
and trigonometry people??

motor has a 57mm stroke and 73 mm bore, I plan on increasing the stroke to 61 mm. the stock rod is 110mm. how much will a 115mm rod decrease the rod angle? Will this change have much of an effect on dwell timing and side load? Motor lives between 5000 and 9000 rpm.

Thanks, I suck at this math stuff.

lohring
04-24-2010, 05:50 PM
Half the stroke divided by the rod length should give the sine of the rod angle. I get 15 degrees for a 57 mm stroke and 110 mm rod. A 61 mm stroke and 115 mm rod gives 15.4 degrees

Lohring Miller

phragle
04-24-2010, 06:18 PM
Is that enough to make any kind of difference??