Primary, secondary reduction ratios.

So I'm trying to make a spread sheet that will give a ground speed for a given engine RPM. My question is what is this Primary reduction ratio that is listed in the KZ model history. is that the reduction from the crank to the primary shaft?? Any help is much appreciated.

There are programs already out there for gear charts that might help you with this:

www.GearingCommander.com

and if you have Excel on your computer:

www.cunnington1.freeserve.co.uk/gearing_v12.xls

Alright got it thanks.

Becker wrote:

My question is what is this Primary reduction ratio that is listed in the KZ model history.

My manual says 57/23 for my 1979 KZ750.

Becker wrote:

is that the reduction from the crank to the primary shaft??

That was my understanding.

Then the reduction to the wheel is the sprocket ratios which was 16/38 (stock) for mine.