[mike_Kilroy]

......I have just begun researching them and am currently basing my choice off what other have used. The one I chose is:

Input Voltage : max. 37V (10S Li-po)
Kv : 250 rpm/V
No. of turn :14 Delta
Max. efficiency current : 50A
Current capacity : 65A/60s
Internal Resistance : 59 mohm
No Load current @ 7V: 2.16A
Number of poles/magnets : 14

ok, so turning this into normal motor data, you are looking for:

Kv=4V/Krpm
Kt=0.067nm/amp (pretty whimpy motor!)

so .067nm/a*50a= 3.3nm continuous torque rating
and if 37v is some max voltage, this puppy will go a max 37v/(4v/krpm)=9,250rpm.....

Not very efficient design..... such low voltage and high current means lots of losses..... I just had a very similar motor designed (10 pole - needs 600hz for 6000rpm - over most drive amplifiers max, let alone 14 pole and 9000rpm) and built for a space station camera application and its efficiency is horrendous. the motor inductance is soooooooo low (27uH), no drive can run it without external inductors, which then cause the voltage required to go up very significantly, so with all the losses, you will probably end up needing 100v bus and loose 1/2 the power in heat in the inductors..... are you open to more reasonable design? if so, what are you really after (torque, speed, physical size, hp ratings)?

so it is rated 50a*1.73*37v=3.2kw or 4hp

1) So you want about 4hp motor good for 8-9000rpm max speed? is this the spec you are after?
2) If so, what is physical size limits? can it be 10" dia x 30" long?
3) is it to be frameless (rotor/stator set)?
4) does it need feedback or will you provide that?

If you add this kind of detail there will probably be a lot more than just me who can give you a list of possible USA manufactures.