Do some motors have more/less torque with the same power levels?

[speedyebikenoob]

If I use the same power motor controller on the cyclone 3000 as I did on the mini, and I gear it to have the same top speed in each gear as my mini, why would the cyclone 3000 have more torque? Where does that extra torque even come from?

It wouldn't. Torque is a function of torque constant (Kt) in Nm/A, amps, and gearing.
The Mini is geared with 9.55:1 primary torque multiplication, whereas the 3000 is geared with 6:1 primary torque multiplication, but the 3000 probably has higher Kt to compensate. So if you use the same controller with the same amps, it wouldn't have more torque -- they would be about the same.

The advantage to the 3000 (as with all larger motors) is that it can take more amps, and for longer, and thus make more torque (and thus power):
cyclone motors.JPG

Okay this makes perfect sense thank you I'm guessing I should expect a small power increase though with a larger motor because it'll be more efficient than the lesser motor right? Less power goes to heat and instead into the wheel where it's supposed to go? Probably a small difference though.

 

[speedyebikenoob]

So it's as I thought then. If they are geared to the same max speed (meaning the winding is irrelevant, right?) and powered with the same controller, they should have the same performance, unless one motor is more efficient than the other. In which case the more efficient motor will have better performance because less power is being wasted by turning into heat.

Am I missing anything here?

That they can be spinning at different speeds and overheating - you can put double the power through the 3 Kw

If the bike and motor were going at the same speed and the only difference between the motors was number of windings and the voltage and current trade off were according to the difference in windings then the windings would be irrelevant.
If you only change the windings and you change the battery configuration then you get exacty the same performance.

In your example we might have to look in a bit more detail at exactly what differs and what you want out of it and what you are prepared to change for an improvement. There are quite a few things to potentially change and they may affect each other differently at different speeds

The motor could be different due to it's size, the amount of copper fill, number of poles etc. Are you able to find out the spec of the two motors and plug them into the grin simulator?
We can then get some better numbers and work out how yours system might actually behave.
I had a quick look and couldn't see the Cyclone.

Are you after more power, more top speed, less overheating, better efficiency, better range?

As you have gears you can be travelling at the same speed but the motor could be spinning at a different speed and the efficiency gains for that can be significant - see my post two posts up. one motor is using 25% more power and overheating in a couple of minutes but it's an identical motor and the bike is going at the same speed.

Changing the windings only, to allow the motor to spin at a different speed, might also have a similar effect - largely due to the efficiency difference due to the motor speed. (Again as this sometimes gets misunderstood, if the motors were spinning at the same speed and otherwise identical, other than windings, then changing the windings wouldn't help efficiency at that speed and you just trade volts for amps to paraphrase Justin)

Unfortunately I have no clue what the specs for the motors are. Couldn't find it in the simulator either I am after reliability though, so less overheating for sure. I like the amount of power and range I have. More top end would be nice, but 45 mph on an e bike is already more than enough for me (which is what it does rn). I basically just want to be able to go full throttle more often without worrying too much about the motor temps, and be able to cruise at a max of 35 mph on a flat road without the bike overheating.

 

[fatty]

Okay this makes perfect sense thank you I'm guessing I should expect a small power increase though with a larger motor because it'll be more efficient than the lesser motor right? Less power goes to heat and instead into the wheel where it's supposed to go? Probably a small difference though.

Not if you use the same (small) controller, which wasn't too lossy on the smaller motor. The larger motor will have less resistive loss, but greater hysteresis and eddy current losses, so it'll mostly balance out.

 

[BobBob]

Unfortunately I have no clue what the specs for the motors are. Couldn't find it in the simulator either I am after reliability though, so less overheating for sure. I like the amount of power and range I have. More top end would be nice, but 45 mph on an e bike is already more than enough for me (which is what it does rn). I basically just want to be able to go full throttle more often without worrying too much about the motor temps, and be able to cruise at a max of 35 mph on a flat road without the bike overheating.

Sounds like a plan, it's designed to handle 3Kw without overheating whereas the old one was designed for 1.8 so the efficiency might not matter as much.
As you already have enough power and range the bigger motor will not overheat as much even if it is just as inefficient because it is able to dissapate more heat. At the same power it will be cooler.
Then if you still want more top end, a higher voltage battery may be the way to go. If the motor is spinning at a higher speed, you should get more power a bit more efficiently, so it won't overheat as much, but that can be stage two. Have a play with the simulator.
Good luck, have fun, let us know how you get on

 

[speedyebikenoob]

Okay this makes perfect sense thank you I'm guessing I should expect a small power increase though with a larger motor because it'll be more efficient than the lesser motor right? Less power goes to heat and instead into the wheel where it's supposed to go? Probably a small difference though.

Not if you use the same (small) controller, which wasn't too lossy on the smaller motor. The larger motor will have less resistive loss, but greater hysteresis and eddy current losses, so it'll mostly balance out.

I'm sure the controller was extremely lossy on the smaller motor though XD. I replaced the stock 40 amp controller with an 80 amp one and was running it at 60v, so quite a lot of power for a small 1680w motor. Can't imagine it being efficient at all. This is the controller I plan to use on the new motor.

 

[speedyebikenoob]

Unfortunately I have no clue what the specs for the motors are. Couldn't find it in the simulator either I am after reliability though, so less overheating for sure. I like the amount of power and range I have. More top end would be nice, but 45 mph on an e bike is already more than enough for me (which is what it does rn). I basically just want to be able to go full throttle more often without worrying too much about the motor temps, and be able to cruise at a max of 35 mph on a flat road without the bike overheating.

Sounds like a plan, it's designed to handle 3Kw without overheating whereas the old one was designed for 1.8 so the efficiency might not matter as much.
As you already have enough power and range the bigger motor will not overheat as much even if it is just as inefficient because it is able to dissapate more heat. At the same power it will be cooler.
Then if you still want more top end, a higher voltage battery may be the way to go. If the motor is spinning at a higher speed, you should get more power a bit more efficiently, so it won't overheat as much, but that can be stage two. Have a play with the simulator.
Good luck, have fun, let us know how you get on

Thanks, just ordered a 4 kw cyclone. Probably overkill but I'm sick of my motor overheating on hills and any speed above 30 lmao. At 60v and 80 amps it shouldn't be too stressed and especially since I'm going to install a temp sensor too, thing should be bulletproof (atleast hopefully)

 

[Chalo]

Sure, run a 2-4kW motor at 5kW. What could possibly go wrong?

I wonder why they rated it 2-4kW?

 

[fatty]

I'm sure the controller was extremely lossy on the smaller motor though XD. I replaced the stock 40 amp controller with an 80 amp one and was running it at 60v, so quite a lot of power for a small 1680w motor. Can't imagine it being efficient at all. This is the controller I plan to use on the new motor.

It would have been helpful to include that in your first post, before a page and a half of errant analysis and commentary.

 

[BobBob]

Thanks, just ordered a 4 kw cyclone. Probably overkill but I'm sick of my motor overheating on hills and any speed above 30 lmao. At 60v and 80 amps it shouldn't be too stressed and especially since I'm going to install a temp sensor too, thing should be bulletproof (atleast hopefully)

lol, so you changed the controller and have just ordered a bigger motor. Can the battery take the extra demand?
Nothing is bulletproof or foolproof but I reckon it will be a whole lot better than the previous one (it will blow up on steeper hills and higher speeds) and you can turn the amps down a bit until you know how hot it gets and have a temperature sensor.

 

[speedyebikenoob]

I'm sure the controller was extremely lossy on the smaller motor though XD. I replaced the stock 40 amp controller with an 80 amp one and was running it at 60v, so quite a lot of power for a small 1680w motor. Can't imagine it being efficient at all. This is the controller I plan to use on the new motor.

It would have been helpful to include that in your first post, before a page and a half of errant analysis and commentary.

Sorry, I didn't think it was relevant when I first posted. 80 amps v. 40 amps isn't the overall concept basically the same anyways?

 

[speedyebikenoob]

Sure, run a 2-4kW motor at 5kW. What could possibly go wrong?

I wonder why they rated it 2-4kW?

1680w* This isn't even the 3 kw cyclone. To its credit though, it lasted over 800 miles of my abuse, and there are quite a few hills around here too. It probably would be a good reliable motor as long as you run it within its rated power. Probably would have lasted a lot longer than 800 miles.

 

[speedyebikenoob]

Thanks, just ordered a 4 kw cyclone. Probably overkill but I'm sick of my motor overheating on hills and any speed above 30 lmao. At 60v and 80 amps it shouldn't be too stressed and especially since I'm going to install a temp sensor too, thing should be bulletproof (atleast hopefully)

lol, so you changed the controller and have just ordered a bigger motor. Can the battery take the extra demand?
Nothing is bulletproof or foolproof but I reckon it will be a whole lot better than the previous one (it will blow up on steeper hills and higher speeds) and you can turn the amps down a bit until you know how hot it gets and have a temperature sensor.

The battery should be able to, the bms is rated at 50 amps continuous and 70 amps burst, so I can just use my cycle analyst to limit the power to under 70 amps. It handled it fine when I was using the more powerful controller on the smaller cyclone motor, never tripped or anything.

The tricky part now is going to be making sure I don't push the battery too hard as with this 4 kw motor I'll definitely be on the throttle more often because I won't be as worried about overheating.

And right yes nothing is bulletproof. At the appropriate power levels though, I never had a problem with the smaller cyclone motor, so given that 2400 watts continuous is within the capability of this motor, hopefully it should be pretty reliable.