I think I have to go along with eddy on this one, MOD1 is a shade OTT on a feather, we have used MOD1.5(HD) on a heavy with Bosch 750s overvolted @ 36V and even that was probably more than was needed!
On Scopion Jr we use a pair of gold 24Vs @ 24V with a ratio of 4.5:1 through 2.5mm pitch, 10mm wide timming belts with 125 dia. wheels, as far as top speed goes Im not sure what it is, but anyone who has seen it drive knows it can take off across the arena like a scalded cat!
On the down side, as Alan rightly says they do run bloody hot!! and Im not convinced that drilling holes in them is the answer. I think the only way to keep them at reasonable temp. is to up the ratio to around 8 or 10:1 and make them work less hard!..down side of course is a serious reduction in speed, but this is in part compensated for by a proportional increase in torque. So at the end of the day, as with most things, you have to find a compromise that works for your machine!
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