904 speedo gear

Nice chart
I upgraded my chart to match. button pushed.
Years ago I committed a formula, that I had worked out, to memory.It basically worked out that at 26.5 inch tire, the toothcount equalled the gear ratio,minus the decimal. Then you adjusted for tire size using percents. So a 2.76 used a 28 tooth, and a 3.91 used a 39 tooth, etc. If your tire was smaller, say 5% or 25.2", you would add 5%teeth, or the 28 becomes 29.4, and the 39 becomes 41. You get the idea. The chart was history.