Who knows anything about rod ratios in aircooled engines.
From the small amount of reading I've done so far, I've worked out a few things (I think)
Rod ratio is the ratio of the length of the conrod/stroke of the crankshaft
Standard
Conrod length (mm) - 136.144
Stroke (mm) - 69
136.144/69 = 1.97
A write up by the late Mark Herbert states that a lower RR will give an engine with more torque, but you shouldn't really go any lower than 1.67, This equates to a 5.4in conrod on an 82mm crankshaft.
What are the upper and lower limits for RR?
Does anybody have real data from experimenting with different ratios in the same engine or know a website with this sort of info on it?
Thanks,
From the small amount of reading I've done so far, I've worked out a few things (I think)
Rod ratio is the ratio of the length of the conrod/stroke of the crankshaft
Standard
Conrod length (mm) - 136.144
Stroke (mm) - 69
136.144/69 = 1.97
A write up by the late Mark Herbert states that a lower RR will give an engine with more torque, but you shouldn't really go any lower than 1.67, This equates to a 5.4in conrod on an 82mm crankshaft.
What are the upper and lower limits for RR?
Does anybody have real data from experimenting with different ratios in the same engine or know a website with this sort of info on it?
Thanks,