The Juice

iTrader: (25)

I am moving out of the slash rtr world into building a jammin scrt. I have read tons of threads on what set up is good but I dont just want to buy something because everyone else is using it, I want to understand how it will affect the car.
I see many people referring to 540, or 550 size motors, I also see them referred to in turns, and kv. I have seen a wide range of kv ratings used in the same car and dont understand how they run the same.
Can someone explain a little about some of the differences in a 540 and 550 motor, and do the turns directly relate to the 540 or 550?

mahamoti

iTrader: (16)

I'm sure someone can explain it better than I can, but this should get you off to a good start:

540/550 describes the size of the motor can. Larger numbers mean bigger can diameter.

Turns and kv are related, in that the lower turn motors are higher kv. Less turns means higher rpm, with less torque.

omegaf

540 and 550 are motor sizes. They just reflect the length of the can's diameter in mm i think. If they are both rated at the same kv then they will both perform the same assuming all the other factors are the same (battery, ESC)
Turns are used for brushed motors. It is a rating scheme based on the gauge of the wire used for the motor windings. This rating is irrelevant in brushless motors. Many have attempted to convert kv to turns but there is no strict conversion.
Kv rating states how many rpm per volt the motor produces. So it directly relates to how many volts you are feeding the motor and your ESC. Obviously higher KV will give you a faster motor but there are lots of factors that determine how the motor behaves in terms of torque and power consumption.

NovakTwo

The 540/550 relate to the length of the motor---550 is longer. Here is our BL Motor Spec Chart, showing side by side comparisons. Sensored motors are generally designated by winds---4.5T, 10.5. etc. Non-sensored motors have traditionally been described by Kvs. We indicate both numbers with our motors.

Novak designs/mfgs only sensored motors, and here is a tech article that we prepared explaining the difference:

BRUSHLESS MOTORS: SENSORED VS. SENSORLESS

We recommend our 550 size motors for 4x4 SCTs because they are more powerful and have a beefier 5mm rotor shaft necessary in the heavier trucks.

TeamNovak Ballistic Spec 540 Motors

TeamNovak Ballistic 550 Motors

RCaddict0

iTrader: (85)

Higher KV is faster with the same amount of voltage. KV= RPM per volt. The higher KV motors/lower turn are more for onroad(5000+) and lower for off road ofcourse. I would recommend a lower KV motor and gearing up for speed. Higher rated motors run hotter, pull more amps from your battery and give you no room for gearing. The lower rated motors are much easier on your esc and batteries. You can easily gear up or buy higher cell lipos to get more speed. For 2wd trucks 540 works, for 4x4 540 would work, but 550 would provide you more torque and run the heavier truck more easily.

The Juice

iTrader: (25)

I'm glad you responded, your 550 5.5 turn is what I'm looking at. So with the longer stator and rotor magnet its basically just a bigger engine, like a v6 to v8 comparison? With more power/torque you don't need as high of a kv rating/rpm, kinda like a foreign rice burner versus american muscle car?

So now onto the esc. Which esc would you say pairs perfectly with the 550 5.5 turn, and why?

Lastly, how do you figure out what C rating on your lipo you need to get the most out of these motors, I haven't seen an amp rating?

Thanks for everyones help.

omegaf

the bigger motor will give more torque but also use more power. just like muscle cars drink like drunkards.
the watt rating will help you figure out the C rating you need. W=A*V you know the watts, you know the volts so you can find the amps. based on that you can find the C rating.
ESC usually have rating on the max turns they can drive. if you load them with a smaller turn motor, you will burn them. Other than that, the choice is yours.

NovakTwo

Here are the current Novak controllers that we combo with our Ballistic 550 motors on 2S; these are low RDS-on (0.00040 ohms) escs necessary for these motors:

GTB2
Havoc Pro SC
Kinetic Spec
Kinetic 2S

Novak's new ESCs:

...GTB2: new features, on-board programmability (no timing) for spec racing, 3.5T 540 motor limit (99.99)

...Havoc Pro SC: new features, on board programmability, including timing adjustments for SC and off road, 3.5T 540 motor limit (139.99)

...Kinetic Spec: new features, full timing adjustments, PC programmability/updateability (NL)--no CL, 8.5T 540 motor limit (159.99)

...Kinetic 2S: everything, full timing adjustments, PC programmability/upgradeability (NL), CL, 3.5T 540 motor limit (199.99)

* all these ESCs are also compatible with Ballistic 550 motors w/2S.

The Juice

iTrader: (25)

Even though they say 540 motor limit they definitely work with the 550? No long term issues?

NovakTwo

No problem on 2S; no long-term issues.

Ironwolf1974

iTrader: (6)

Ok so I have a GTB 2 and going to get a Losi Ten SCTE. What motor should I throw in there for 2s racing?