Bearings must run hot at those speeds

The Novak motors are rated unloaded I believe, which always gives much higher numbers. The Castle motors are rated under load, though; the 9000 will be a fair bit faster than a 3.5R.:wink:

This motor on 2s will not be any faster than than a cms 5700 motor on 3s.

9,000 x 7.4 = 66,600 rpm
5,700 x 11.1 = 63,270 rpm

And if you take into acount that the 5700 setup will be slightly more efficient than the 9,000 kv setup, you will be able to gear the 5700 up to match the rpm at the wheels. Not only that, but the esc will create more than twice as much heat with the 9000 kv setup.

So no need for there to be anything special for the rotor or bearings compared to the current existing motors.

If they are giving the motor 100k rpm specs it must use good bearings, and some sort of rotor wrap...

Actually Patrick said a while back they changed all of the cm36's to be 100k motors.

The 9000 will be no more or less efficient. While lower KV motors use lower amperage to hit a given RPM, the wind resistance is higher so it is a wash. Efficiency is dependent on construction and load, not KV.

That would be correct sir!

New bearings, new magnet, new glue, heck, new almost everything.

Sweet! I've got an older CM36-5700 which finally gave up the ghost, even the old ones were tough as nails. When will the 9,000s be shipping? I'm looking at buying a street car and that would be a nice motor for it.

Is there any way of knowing these motors over the old ones?

Yes -- new connectors on the new motors. If you have the split type connector, it is the newer motor. If you have the banana type connector (with the twirly bit on the male side) you have the old motor.

any chance of a lower kv motor...like 3k ish?

Yep -- coming soon.

We are also working on a motor that will be sorta half-way between a 1515 and a CM36. So-- very fast 4s 10th buggies (read lotsa broken parts!) or more mild 1/8th buggies and 1/10th monster trucks.

Ah that might be a interesting motor to try out.

Sounds like a 1512 :whistle:

Well, I meant in output watts.... the 1512 is almost the same output power as a 1515.