What kv brushless motor for a mini boat?

[lucozader]

i have some 2600kv 2030 motors and they are great

i see some 4000kv and 5000kv 2030 motors for sale

from tenshock and feigao

would these not be too fast and have too little torque ?

[sailr]

Higher KV motors (4000-5000) require you run less volts. The best performance for a mini is 3200-3800KV on 11.1V. You MIGHT get by with a 3S on 4000 but would need to step down to 7.4V on 5000. Also, as you go up in KV, you need to reduce the prop size.

Give us some more details of your boat.

[Simon.O.]

You MIGHT get by with a 3S on 4000 but would need to step down to 7.4V on 5000. Also, as you go up in KV, you need to reduce the prop size.

Give us some more details of your boat.

In 2 of my smaller hulls I have a 4000kv Heli motor on 3S but also run a small 427 prop. A 432 gets things real hot real fast.
One of my riggers has run a 5000kv Feigao on 3S but I do not reccomend that.

Higher volts (3S) means you can use a smaller esc and there is less stress on parts all round.
Another advantage of 3S is that there are a lot of motors (different kv values) so you can match a projected shaft rpm and prop easily to determine performance.

With a 2600kv motor you could go 4S, if you can find a nice small 4S pack to fit the hull or even a pair of 2S in series. I'll be doing this soon with one of my riggers and a 2980kv motor.

[lucozader]

here is a vid of the boat

http://www.youtube.com/watch?v=SwwuD_fjxMo

it has a 2600kv motor now

i might try a 4200kv motor now and see how it goes