Kyosho Inferno GT2 VE - Big-Block Edition

[Dr_T]

Hmmm..., so here I was thinking I had it all figured out and wanting to prove the world my jumbo pinion was not a stupid idea... LOL... Maybe it is indeed better to go a bit higher kv...

A motor that spins twice as fast, needs to deliver only half of the Torque in order to put out the same mechanical Power (Torque*angular velocity of shaft). Torque is proportional to I/kv, in other words, Current is proportional to T*kv; so with half the Torque and double the kv, the Current actually stays the same. The difference however is that the the higher kv motor, has less windings / turns and thus lower copper resistance (which adds up more when it's a quality motor)... So from a copper (I^2*R) losses point of view, RPM should indeed be as high as possible. Non-copper (core and mechanical) losses however, increase with increasing RPM, so the big question is: where's the sweet-spot?

Bruno actually has a 2200 kv TP5670 on sale, that needs a 400+ A ESC for full potential... so maybe not :). MBP has what seems to be an old (yellow 3 piece design) TP5840S-4Y, 1600kv (31 V max, 270 A, 715 g). There's also a TP5660-6D 1420 kv (old specs: 35V max, 285 A, 835 g) I'm considering. 36/36 gearing will probably be a bit too tight, but 36/40 and 40/40 light and cheap Revo gears will fit and give nice speed range:



Have to sleep on it :).