Zero369

I been doing a lot of research on BL motors and watts, amps and all that good stuff. I found a very interesting stats in two way different motors, have a look.




Traxxas Velineon 3500 Brushless Motor
Watts: 481 on 7.4v, 721.5 on 11.1v, 917 on 780 on 12V
RPM/volt: 3500 (10-turn)
Max RMP: 50,000
Current Ratings: 65A constant / 100A peak/burst
38,850 RPM on 3s Lipo 11.1v - 65 Amps @ 721.5 Watts



Novak Ballistic Racing Brushless Motor 6.5T
Watts: 390
kV: 6400 RPM/volt (unloaded)
Lipo
71,040 RPM on 3s Lipo 11.1v - 35.1 Amps @ 390 Watts



I would of thought the bigger motor would pull more watts out, but in this case the smaller one is gonna be stupid fast off the line. Unfortunately, the bigger motor does pull way more RPMs; just about double that of the Velineon, 32,190 more RPMs to be exact so it is way fast in the top speed department. Of course, these motors should be looked at in being in the same RC with the same setup and such. Also, I am not sure what the max RPM and max voltage is on the Novak, but in itself the number are pretty cool.

Anyways, I just wanted to share something that I thought was really cool. I am finding all kinds of numbers on these BL motors and lipo that just fascinate me. Sorry if I bored anyone .

Edit: Another cool comparision to a 5000kv...
Novak Ballistic Racing Brushless Motor 8.5T
Watts: 280
kV: 5000 RPM/volt (unloaded)
Lipo
55,500 RPM on 3s Lipo 11.1v - 25.2 Amps @ 280 Watts

If the this motor was on 2s Lipo 7.4v; then the Velineon would give it a run for its money
37,000 RPM on 2s Lipo 7.4v - 37.8 Amps @ 280 Watts

Ray

ScottStaypuff

I would take the lower kv motor with higher wattage any day! Thanks for posting the info. I'd like to see the same for the Castle motors.

BigTb17

Your numbers all look correct. Just keep in mind, those ratings aren't the maximum it will pull (390 watts for the Novak, and 65 amps for the Traxxas). Those are the maximums it is rated for.

If you ran that 6.5 turn (6400KV) Novak on 11.1 volts and geared it too high, it may pull way more amperage and wattage than that. The problem is that it would overheat very quickly. You have to gear it so the load on it never causes it to draw any more than 390 watts.

With the Traxxas motor, you would still have to gear so it isn't pulling more than that. You just have more gearing room since it is rated higher.

You can virtually always pull more amperage than a motor is rated for. I have a small airplane motor that is only rated for 7 amps, but I was doing some testing and something bound up for a second, and the amps went well over 20 momentarily, and the motor got very warm almost instantly. If I had kept going at that much amp draw I would have burnt up that motor very quickly.

It's a similar scenario with those motors you listed above. If you gear them too high, or put them in too large a car with tires that are too big (anything that puts too much load on them) they will pull higher than they are rated for. The trick is to set them up so that they don't pull any more than their maximum.

Your numbers and conclusions aren't wrong, I'm not saying that. I simply wanted to clarify (just in case people were getting the wrong idea about the ratings) that the specs on a motor aren't what it will pull, they are what it is rated to be be able to safely pull. It is up to whoever is using them to put them in a proper application and gear them accordingly.

Access

Don't place too much importance upon the numbers that manufacturers put out, I think most of us have found that in practice, the numbers are next to irrelevant. Some companies rate their motors, ESCs, etc. anywhere from 33% to 300% of what others do, but in reality, one 580 motor is going to be roughly the same as the next.

With brushless, torque, power, etc. are so excessive for the vehicle size, it's rare to have a brushless setup that struggles to get to full speed in under 2 seconds or so (traction allowing). The only statistic that really matters is efficiency and again that is not reliably spec'ed by the different manufacturers out there. Efficiency is important b'cos it keeps things cool, rather than heat running away (hotter motor -> less efficient -> even hotter motor) and so on.

Zero369

@ BigTb17
Yeah I totally agree with everything you stated for sure! Just think... this past weekend I didn't know anything about BL numbers or specs and I certainly didn't know how to figure the numbers like I do now. Its amazing what a little determination and help from others can produce .

@ Access
Very good point! I think in some sense, the numbers are important to look at but not the only thing to look at. I would much rather see the numbers on a electric motor dyno than these numbers anyhow, but the numbers do give a somewhat inside look at the potential of the motor. These numbers along with dyno stats, Esc stats, and battery stats, along with real hands-on testing in a car is far more better than just looking at the numbers in itself.

Ray

ElectricGuy007

The Novak motor will be more efficent because it's sensored. It's makes me think alot seeing these numbers.
The traxxas motor was designed for thier vechicles not a pure bred racer. The Novak's have been tested in race machines.
I've already seen a thread somewhere where they took the motors apart and compared the quality.
I bet you would see a heck of a difference there, because they are made in different factories.