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Bafang motor upgrade comparison

Started by Altema, January 19, 2021, 02:12:31 PM

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springer03

#30
Altema
The windings are bigger in the Rad motor. I've pulled the motors the rest of the way apart and measured them directly. The stator coil windings on the Rad motor are 0.65mm in diameter. On the upgrade motor they are 0.55mm.
[/quote]

Do you think the 7 strand version would equal the size difference? And have any "noticeable" feel in your hill climb test?
Just curious, I'm not going to bother exchanging for a small difference.  I would have upgraded the motor for the increased speed anyway but more torque would have been nice.

Altema

Quote from: springer03 on February 07, 2021, 02:18:38 PM
Do you think the 7 strand version would equal the size difference? And have any "noticeable" feel in your hill climb test?
Just curious, I'm not going to bother exchanging for a small difference.  I would have upgraded the motor for the increased speed anyway but more torque would have been nice.
The locked rotor and low RPM torque of the Rad motor is a bit better, but the upgrade motor feels like it has a fatter torque curve above 10 mph. In the hill climb test, the Rad motor does better from a dead stop or from a very low RPM. I had to put one food down for stability because the back tire was slipping and chewing up the grass (sorry city workers!). The upgrade motor made it up the 28% grade also, but without quite as much authority.

But, severe hill climbs are a niche scenario, and once you get above a few MPH, the upgrade motor becomes more fun. I'm choosing to keep the upgrade motor in because I have more situations where the top end is important.

springer03

Quote from: Altema on February 08, 2021, 07:09:49 AM
Quote from: springer03 on February 07, 2021, 02:18:38 PM
Do you think the 7 strand version would equal the size difference? And have any "noticeable" feel in your hill climb test?
Just curious, I'm not going to bother exchanging for a small difference.  I would have upgraded the motor for the increased speed anyway but more torque would have been nice.
The locked rotor and low RPM torque of the Rad motor is a bit better, but the upgrade motor feels like it has a fatter torque curve above 10 mph. In the hill climb test, the Rad motor does better from a dead stop or from a very low RPM. I had to put one food down for stability because the back tire was slipping and chewing up the grass (sorry city workers!). The upgrade motor made it up the 28% grade also, but without quite as much authority.

But, severe hill climbs are a niche scenario, and once you get above a few MPH, the upgrade motor becomes more fun. I'm choosing to keep the upgrade motor in because I have more situations where the top end is important.

Thanks
If I seen this thread before I ordered it I probably would have ordered Electric bike worlds motor with the 7 strand instead of 6, but I'm sure I'll be happy with the upgrade from stock. Once I get the new controller kit I'll put them in at the same time.
Thanks for taking the time for your testing 👍

fin_rad

#33
Interesting, I contacted the Bafang support by email and asked them to check the motor model from its serial number... And they answered it is a 500W.

Edit: typos

Altema

Quote from: fin_rad on February 08, 2021, 08:15:55 PM
Interesting, I contacted the Bafang support by email and asked them to check the motor model from its serial number... And they answered it is a 500W. Does not change
On which motor?

fin_rad

My ebike is the RadRhino 750W EU my 2019, if that's what you asked? Original one, I have not changed it (yet :) ).

Altema

Quote from: fin_rad on February 08, 2021, 09:36:09 PM
My ebike is the RadRhino 750W EU my 2019, if that's what you asked? Original one, I have not changed it (yet :) ).
Yes, that is what I asked. We were talking about so many different models, I just wanted to make sure 😊

JTK77

#37
Quote from: Altema on February 07, 2021, 01:42:47 PM
Quote from: JTK77 on February 03, 2021, 10:31:33 AM
Yes. Multistrand winding enables more copper fill. That's why the G060.750 can have thinner coil strand but still faster kv (in this case).
In overall the efficiency increases little but this is mostly beneficial in terms of fewer watts wasted in overheating as copperlosses. The difference naturally increases with more power used and is further effected by the increased copper temperature (increase in R).
I had the 750+52v+35A setup few years back but now running vented G062.1000 at 60v 40A..and going soon to custom 45-50A sinewave and custom 60v 24Ah 150A BT battery.
Just to be clear, the windings on both motors is single strand solid core copper. The Rad kV cannot be determined because the internal limiter prevents the motor from reaching it's natural freewheel RPM.

What controller are you using for your new setup? I'm keeping my eye out for a sinewave controller instead of the cheap trapezoidal wave controller like I have now. It gets the job done and put 1600 watts through the stock Rad motor for 600 miles, but the noise and lack of efficiency still annoys me.

Yes, the strands are single but every "turn count" is made of bundle of these wires (bundle is "multistrand").
The speed limiter is in the controller. On stock one you can set speed to 40kmh and change wheel size to min and then test no load speed calculating back to correct wheel size. With LCD3 or LCD8h you only need to play with wheel size is no load speed is more than 72kmh (I have currently just over 80kpm with current setup)
The new controller kit is custom KT version. The idea is cost effective Plug n play kit for 48v to 60v batteries. Will be verions for G060 (z916 motor cable) and G062 (L10 motor cable). Battery connection 10awg with xt90. PCB will be conformal coated.

Altema

Quote from: JTK77 on February 10, 2021, 01:59:33 AM
Quote from: Altema on February 07, 2021, 01:42:47 PM
Quote from: JTK77 on February 03, 2021, 10:31:33 AM
Yes. Multistrand winding enables more copper fill. That's why the G060.750 can have thinner coil strand but still faster kv (in this case).
In overall the efficiency increases little but this is mostly beneficial in terms of fewer watts wasted in overheating as copperlosses. The difference naturally increases with more power used and is further effected by the increased copper temperature (increase in R).
I had the 750+52v+35A setup few years back but now running vented G062.1000 at 60v 40A..and going soon to custom 45-50A sinewave and custom 60v 24Ah 150A BT battery.
Just to be clear, the windings on both motors is single strand solid core copper. The Rad kV cannot be determined because the internal limiter prevents the motor from reaching it's natural freewheel RPM.

What controller are you using for your new setup? I'm keeping my eye out for a sinewave controller instead of the cheap trapezoidal wave controller like I have now. It gets the job done and put 1600 watts through the stock Rad motor for 600 miles, but the noise and lack of efficiency still annoys me.

Yes, the strands are single but every "turn count" is made of bundle of these wires (bundle is "multistrand").
The speed limiter is in the controller. On stock one you can set speed to 40kmh and change wheel size to min and then test no load speed calculating back to correct wheel size. With LCD3 or LCD8h you only need to play with wheel size is no load speed is more than 72kmh (I have currently just over 80kpm with current setup)
The new controller kit is custom KT version. The idea is cost effective Plug n play kit for 48v to 60v batteries. Will be verions for G060 (z916 motor cable) and G062 (L10 motor cable). Battery connection 10awg with xt90. PCB will be conformal coated.
Understood on the bundles. I've had three different controllers on this particular Rad motor, and the no load speed is 40km even if set to 70km. You can watch the power being throttled above 32km regardless of controller, so that makes me think the motor has an RPM limiter.

Your controller sounds interesting, so let me know if you start selling them. I always prefer the XT90, and use the sparkless version for batteries. My rack battery came with the mid size Anderson connector, which I feel is inferior and bulky. I could not find a panel mount version of the XT90, so I had to use the XT60 for accessory connections to the rack battery.

JTK77

Quote from: Altema on February 10, 2021, 07:39:01 AM
Quote from: JTK77 on February 10, 2021, 01:59:33 AM
Quote from: Altema on February 07, 2021, 01:42:47 PM
Quote from: JTK77 on February 03, 2021, 10:31:33 AM
Yes. Multistrand winding enables more copper fill. That's why the G060.750 can have thinner coil strand but still faster kv (in this case).
In overall the efficiency increases little but this is mostly beneficial in terms of fewer watts wasted in overheating as copperlosses. The difference naturally increases with more power used and is further effected by the increased copper temperature (increase in R).
I had the 750+52v+35A setup few years back but now running vented G062.1000 at 60v 40A..and going soon to custom 45-50A sinewave and custom 60v 24Ah 150A BT battery.
Just to be clear, the windings on both motors is single strand solid core copper. The Rad kV cannot be determined because the internal limiter prevents the motor from reaching it's natural freewheel RPM.

What controller are you using for your new setup? I'm keeping my eye out for a sinewave controller instead of the cheap trapezoidal wave controller like I have now. It gets the job done and put 1600 watts through the stock Rad motor for 600 miles, but the noise and lack of efficiency still annoys me.

Yes, the strands are single but every "turn count" is made of bundle of these wires (bundle is "multistrand").
The speed limiter is in the controller. On stock one you can set speed to 40kmh and change wheel size to min and then test no load speed calculating back to correct wheel size. With LCD3 or LCD8h you only need to play with wheel size is no load speed is more than 72kmh (I have currently just over 80kpm with current setup)
The new controller kit is custom KT version. The idea is cost effective Plug n play kit for 48v to 60v batteries. Will be verions for G060 (z916 motor cable) and G062 (L10 motor cable). Battery connection 10awg with xt90. PCB will be conformal coated.
Understood on the bundles. I've had three different controllers on this particular Rad motor, and the no load speed is 40km even if set to 70km. You can watch the power being throttled above 32km regardless of controller, so that makes me think the motor has an RPM limiter.

Your controller sounds interesting, so let me know if you start selling them. I always prefer the XT90, and use the sparkless version for batteries. My rack battery came with the mid size Anderson connector, which I feel is inferior and bulky. I could not find a panel mount version of the XT90, so I had to use the XT60 for accessory connections to the rack battery.

Ok. What voltage battery are you using for the Rad motor? Seems then you are hitting the no load rpm...changing controller wont have effect. This attached picture is simulated performance of G060.500 (stock Rad) with 48v battery and 2 different existing winding versions on Rover. There are one or two more. One in the middle and one might be even slower.

Altema

I'm using 52 volt batteries, and did my test with a near-full charge of 58.3 volts. Would the cutoff when hitting the no load RPM be that sudden? The motor pulls around 1500 watts at 20mph, then drops to 200 watts at 23? I'm just asking because the behavior seems odd.

JTK77

#41
Quote from: Altema on February 10, 2021, 06:07:36 PM
I'm using 52 volt batteries, and did my test with a near-full charge of 58.3 volts. Would the cutoff when hitting the no load RPM be that sudden? The motor pulls around 1500 watts at 20mph, then drops to 200 watts at 23? I'm just asking because the behavior seems odd.

What controller and display do you have? What wheel size setting and max speed setting? What exact when speed rear wheel of the ground and full throttle (and what voltage at that moment on display)? Any marking on the motor casing from Bafang?
Speed of 23 mph on Rover requires ~500w of power...so you need quite heavy pedaling effort (~300w) at 23 mph?
Typically 5 to 7 mph from peak power speed to no load speed.

Altema

Quote from: JTK77 on February 11, 2021, 12:08:29 AM
Quote from: Altema on February 10, 2021, 06:07:36 PM
I'm using 52 volt batteries, and did my test with a near-full charge of 58.3 volts. Would the cutoff when hitting the no load RPM be that sudden? The motor pulls around 1500 watts at 20mph, then drops to 200 watts at 23? I'm just asking because the behavior seems odd.

What controller and display do you have? What wheel size setting and max speed setting? What exact when speed rear wheel of the ground and full throttle (and what voltage at that moment on display)? Any marking on the motor casing from Bafang?
Speed of 23 mph on Rover requires ~500w of power...so you need quite heavy pedaling effort (~300w) at 23 mph?
Typically 5 to 7 mph from peak power speed to no load speed.
Controller is the 35 amp version sold by Electro Bike World and Bolton. Display is the usual KT-LCD3. Wheel size is set to  23 inches, actual wheel diameter is 22. 23 was the most accurate according to GPS. Wheel speed is 351.592, which makes the motor RPM 1757.96 because of the 5x gear reduction. I erred in the last post, and looking back through my notes the voltage was 54.0, not 58.3. The Radmini would require less effort due to the smaller diameter wheel, perhaps that's why it was pulling 200? By 23 mph, it was barely, and took a while getting there. If there is no limiter in the Rad motor, then the rating is 32.55 kV.

JTK77

#43
Quote from: Altema on February 12, 2021, 06:58:16 PM
Quote from: JTK77 on February 11, 2021, 12:08:29 AM
Quote from: Altema on February 10, 2021, 06:07:36 PM
I'm using 52 volt batteries, and did my test with a near-full charge of 58.3 volts. Would the cutoff when hitting the no load RPM be that sudden? The motor pulls around 1500 watts at 20mph, then drops to 200 watts at 23? I'm just asking because the behavior seems odd.

What controller and display do you have? What wheel size setting and max speed setting? What exact when speed rear wheel of the ground and full throttle (and what voltage at that moment on display)? Any marking on the motor casing from Bafang?
Speed of 23 mph on Rover requires ~500w of power...so you need quite heavy pedaling effort (~300w) at 23 mph?
Typically 5 to 7 mph from peak power speed to no load speed.
Controller is the 35 amp version sold by Electro Bike World and Bolton. Display is the usual KT-LCD3. Wheel size is set to  23 inches, actual wheel diameter is 22. 23 was the most accurate according to GPS. Wheel speed is 351.592, which makes the motor RPM 1757.96 because of the 5x gear reduction. I erred in the last post, and looking back through my notes the voltage was 54.0, not 58.3. The Radmini would require less effort due to the smaller diameter wheel, perhaps that's why it was pulling 200? By 23 mph, it was barely, and took a while getting there. If there is no limiter in the Rad motor, then the rating is 32.55 kV.

Sorry. Just now realized you have mini! That explains it surely. Your speed matches the 750w motor with winding label (7).

Altema

Quote from: JTK77 on February 13, 2021, 04:51:39 AM
Quote from: Altema on February 12, 2021, 06:58:16 PM
Quote from: JTK77 on February 11, 2021, 12:08:29 AM
Quote from: Altema on February 10, 2021, 06:07:36 PM
I'm using 52 volt batteries, and did my test with a near-full charge of 58.3 volts. Would the cutoff when hitting the no load RPM be that sudden? The motor pulls around 1500 watts at 20mph, then drops to 200 watts at 23? I'm just asking because the behavior seems odd.

What controller and display do you have? What wheel size setting and max speed setting? What exact when speed rear wheel of the ground and full throttle (and what voltage at that moment on display)? Any marking on the motor casing from Bafang?
Speed of 23 mph on Rover requires ~500w of power...so you need quite heavy pedaling effort (~300w) at 23 mph?
Typically 5 to 7 mph from peak power speed to no load speed.
Controller is the 35 amp version sold by Electro Bike World and Bolton. Display is the usual KT-LCD3. Wheel size is set to  23 inches, actual wheel diameter is 22. 23 was the most accurate according to GPS. Wheel speed is 351.592, which makes the motor RPM 1757.96 because of the 5x gear reduction. I erred in the last post, and looking back through my notes the voltage was 54.0, not 58.3. The Radmini would require less effort due to the smaller diameter wheel, perhaps that's why it was pulling 200? By 23 mph, it was barely, and took a while getting there. If there is no limiter in the Rad motor, then the rating is 32.55 kV.

Sorry. Just now realized you have mini! That explains it surely. Your speed matches the 750w motor with winding label (7).
Ok, thanks. You've been most helpful.