mm/5700 TC3 questions. torque/gearing

[phildogg]

I have a question on motor torque/gearing in my TC3. Right now I'm running the mm/5700 on 2s geared 28/72(speed runs).I have ran 48mph on the 2s which Brians calc says is about right. My question is some of the gearing I see really high when doing speed runs(35/60) my question is how much does the torque of this particular motor increase when going up in voltage?(3s,4s) Where is the limit of gearing on 2s? could I gear 30/60 on 2s or does it need the extra volts/torque to pull that gearing? I might be over thinking this also.lmk what you guys think..

[simplechamp]

With 30/60 gearing your rollout will be about 1.6 which is definitely within reason for speed runs. On 2s you're looking at around 40k rpm, but on 3s you would be looking at closer to 60k rpm which I believe is pushing the Mamba 5700 to or past its limits. I think if you need more torque it would be better to go with a lower kv motor and higher voltage. Lower kv = more turns = stronger magnetic field = higher torque at a given voltage, but of course you would be sacrificing some speed.

[phildogg]

anyone else?
phil

[snellemin]

Go to 3s and work from there. That motor has plenty of torque for your TC3. If you do decide to go crazy with gearing on 3s, I suggest adding some more caps.