Quote:

My Speedmaster came with a 16 tooth. I changed it to a 17 tooth after had modified the engine some to get more power. There was slight difference. That changes the ratio only slightly. I think it was maybe only a couple of 100 less rpm at 70 mph. I changed it back to the 16.



If the motor in my 07SM had near stock power then I would definitely run a 16T.

Personally, I wouldn't even consider a 19T, in my area, on anything less than a built 904. And then, if a 904, it would likely run a 17T or 18T.

And the hills where I am located are nothing like the Rockies or Cascades.