Originally Posted by evochick

For 13.5 you realistically only need 2 spurs, a 96T which is readily available and a 97T to give you some in between ratios.

I usually carry pinions from 46 to 56, this gives me a good range, from high speed outdoor tracks to small indoor tracks. 4.1 to 3.4 should be enough range for an Orca TX, but you may need to go lower on really small tracks, which you still can do with the 96T spur.

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