Greetings,
I am planning a custom commuter build. I have a couple of criteria that offer a challenge:
- Rear hub motor with cassette
- Cruising speed 50kph, max speed 60kph on flats. Manageable with aero road handlebars and 1300W peak power (1050W motor, 250W legs).
- Decent torque and acceleration
- Lightweight
60kph in a 29" wheel is about 450rpm, so I will require roughly 450 * 1.2 = 540 unloaded rpm. This is my target. Please correct me if I am wrong!
I've settled on a Q128C. They're very lightweight and said to handle 1000W without much trouble. There are four versions of it:
36V 201rpm = 5.58rpm/V
36V 328rpm = 9.11rpm/V
48V 201rpm = 4.19rpm/V
48V 328rpm = 6.83rpm/V
36V/328rpm would be the obvious choice, it'll only need 60V to reach the desired rpm. However I'm doubtful that it'll have much torque due to being wound so fast.
The next fastest is 48V/328rpm. It'll require a whopping 80V for the desired rpm. Which means 22s battery and a very limited controller selection. On the other hand, more torque. And trouble managing phase current??
The other two motor versions I will disregard.
What do you think? Which variant is preferable? Are there any other glaring flaws in my plan?
Thanks a lot!
I am planning a custom commuter build. I have a couple of criteria that offer a challenge:
- Rear hub motor with cassette
- Cruising speed 50kph, max speed 60kph on flats. Manageable with aero road handlebars and 1300W peak power (1050W motor, 250W legs).
- Decent torque and acceleration
- Lightweight
60kph in a 29" wheel is about 450rpm, so I will require roughly 450 * 1.2 = 540 unloaded rpm. This is my target. Please correct me if I am wrong!
I've settled on a Q128C. They're very lightweight and said to handle 1000W without much trouble. There are four versions of it:
36V 201rpm = 5.58rpm/V
36V 328rpm = 9.11rpm/V
48V 201rpm = 4.19rpm/V
48V 328rpm = 6.83rpm/V
36V/328rpm would be the obvious choice, it'll only need 60V to reach the desired rpm. However I'm doubtful that it'll have much torque due to being wound so fast.
The next fastest is 48V/328rpm. It'll require a whopping 80V for the desired rpm. Which means 22s battery and a very limited controller selection. On the other hand, more torque. And trouble managing phase current??
The other two motor versions I will disregard.
What do you think? Which variant is preferable? Are there any other glaring flaws in my plan?
Thanks a lot!