ok a gobbledygook explanation
the first chart gives the available gear ratios for each gear
the wheel and pinion number in the vertical columns are the number of teeth on the drive and driven gears
simplified by calling each selection for each gear by letters a to b which then transfers to the speed chart
on the speed chart
it is based on using a 4.15/7.15 17" dunlop rear tyre at 12000 rpm
along the top row are the 2 possible primary gear ratios between crankshaft and gearbox 46/20 or 41/18
next row down are the final gearing of gearbox sprocket and rear wheel sprocket
gears 1st to 6th are vertical down the left hand side
the letters are the identifiers for the available ratios for each gear
by following across and vertical the speed in kph is then shown where the 2 cross for each gear ratio
by using these charts it simplifies the selection of gearbox ratios and overall gearing for each circuit/session
with the combination of 2 different primary gears and up to 6 individual ratios for each gear plus gearbox and rear wheel sprocket the possibilities are huge
a complete gearbox removal rebuild and installation took about 20 mins and could be done with the engine in the frame
i hope that simplifies things for the non technical amongst us
hope my memory got all that right from 20 years ago....lol