6 pole motor and 9920

[steveo]

i have a new 9920 and a 6 pole motor for a boat, will the esc handle 6 or can it only do two pole

[squeeforever]

2 polers only. It couldn't even handle a 4 pole, much less a 6.

[steveo]

well i did try it and it ran, there was a slight stutter at top end it was unloaded of course, so dont even try to use is that what you are saying

[What's_nitro?]

I believe the BK controllers have a Max RPM of 40k with 2-pole motors. You can certainly run motors with more poles, but there are things you need to know. A 4-pole motor will require twice the number of pulses from the ESC to operate properly at the same RPM as a 2-pole motor. So with a 2-pole limit of 40k RPM, that would be a 20k limit with a 4-pole motor. You could use a 6-pole motor as well, but the MAX allowable RPM would be way too low for use in a car/truck because you would have to gear really high to get any speed out of it. Now if you had a rock crawler, that would be fine.

[squeeforever]

Actually, I think its more like 150k rpm's, not positive though. You can try it, but the Bk's don't perform that well with them from what I've heard. Alot of cogging mostly. I guess it wouldn't hurt to try though...

[What's_nitro?]

150k? I think you mean the MGM's. My 12020 said it was 40k MAX. It makes sense because I tried to bench test it with an XL 5000 on 3s a while back and it would constantly cog around 3/4 throttle; which happens to be where it hit the 40k limit.

[lutach]

It depends on the controller. The Warriors 99 amps and less and the Microcar 70 amps and less will go up to 150K rpm, but the big guys like the 3695, 36120 for example will only go to 42K rpm on 2 pole motors. The manual on my 3695 says it will go up to 150K rpm, but it is not true.

[What's_nitro?]

Well whatever it is, you just have to remember to divide the max RPM depending on how many poles the motor has:

2 pole = RPM/1,
4 pole = RPM/2,
6 pole = RPM/3,

and so on.

[steveo]

thanks for the replays, i will give it a try i'll just be real gentle and if it dont like it the esc goes back in the truck, i am waiting on funds for a cc hydra 240 to run in all the boats, you all all understand where i'm going from, just cant stand to wait

[lutach]

http://www.bk-electronics.com/man_warrior_eng.pdf

100K rpm for 2 poles
50K rpm for 4 poles
25K rpm for 6 poles

The manual for the Warrior and MicroCar seems to be the same, but my 3695 only spins a 2 pole motor to 42K rpm and it was also confirmed by Barbara from BK.