Slipper and tranny questions

[Sneeck]

RCM has their own metal idler gear's.

As for gearing ratio's, 66/16 which is 4.12. For the strobe slipper you'll need 51/12 which is 4.25, or 51/13 which is 3,92 but that will run slightly faster. So you need the 51 tooth spur gear and mod 1 12 or 13 tooth pinion gear.

I'd get the strobe over the rrp.