My Bensu Clone came with 12:1 gears, but with an 8 tooth pinion gear, which results in 7.25:1 (approximately). I bought the Microsizer axle/gear set, and got the following:
1. Tomy axles are .0035" larger, so I had to bore out mt chassis
2. With the 8 tooth pinion, most of the standard color combo gears didn't work well, but I did get a few good combos to run.
Blue spur / orange axle (best running)- 7:1
orange / aqua- 5.65:1
orange / orange- 6.25:1
I couldn't use the aqua spur at all, because the mesh was too tight, and would bind, and I couldn't use the 6 tooth pinion, as it wouldn't contact the spur at all.
I don't know if this helps anyone, but it'll work for the gee-whiz file.