Maybe this will help? However, unless you are lucky enough to obtain the matched set for your drive train (both the drive and driven gears), you'd probably be better off buying an adapter that matches your drive train and tires exactly (as provided by The Speedometer Shop and others). Those of us that have done this have reported results with 1% or less error.
The link to the chart shows that I should have 4-12 teeth on my speedometer gears if I am using 6.00-16 tires. I am reading this as the gear that mounts on the yoke should have 4 teeth and the other gear should have 12 teeth. I am interpreting that the 4 yoke gear teeth as having 4 teeth minimum at certain points. (I hope I described that clearly enough.) Not as the tip of one gear tooth, then 2 teeth, then the tip of another gear tooth.
I know I can get an adapter from Patrick's Truck.
Any thoughts?
Walt Williams
La Verkin, UT
