REVIEW: QR-E 250W ELECTRIC BOOSTER BICYCLE MOTOR AND B60i AND B70 BATTERY

[ybao]

As someone who loves e-bikes, I truly enjoy admiring these models.
The Qiroll e-bike attracts me with its delicate design and light, elegant character, and it would be even more appealing with the addition of a pedal-assist (PAS) cadence-sensing system.
I also came across the GBoost e-bike, which stands out for its strong climbing capability, giving it a confident and capable presence.

GOOST ebike

 

[3dxl]

My Qiroll Pro still powering good on my bike in 2026 during daily commute. No problem. Battery still runs well since my first post. Anyone still rocking Qiroll?

Video:

 

[3dxl]

Another bike with Qiroll Pro (latest version) still alive after daily abuse on all weather. However it started to sound like turbine jet like the first one if i keep boosting/throttle up. I suspect the inner clutch was loose or grinding along.

 

[BluePixel]

View attachment 208574
Another bike with Qiroll Pro (latest version) still alive after daily abuse on all weather. However it started to sound like turbine jet like the first one if i keep boosting/throttle up. I suspect the inner clutch was loose or grinding along.

I had the same problem. Today I decided to teardown the motor as deep I could without destroying it... And I have good news. Behind the Metal Discs on the side of arm (on Mute Pro: plastic design parts) there are the screws which fixate the motor. I took the screws out and pried the black plastic sides on the motor off. I didn't got deeper than this but I cleaned everything and put some oil on the barrings ( I don't know if it was a good idea) and screwed everything back in place. And now it is silent again . I don't know if it was the oil or the cleaning or both feel free to test...

I think there are no gears or clutch inside because of the very clear magnet fixation you can feel while turning it slowly with your hand. That's definitely a good thing for robustness.

 

[3dxl]

I had the same problem. Today I decided to teardown the motor as deep I could without destroying it... And I have good news. Behind the Metal Discs on the side of arm (on Mute Pro: plastic design parts) there are the screws which fixate the motor. I took the screws out and pried the black plastic sides on the motor off. I didn't got deeper than this but I cleaned everything and put some oil on the barrings ( I don't know if it was a good idea) and screwed everything back in place. And now it is silent again . I don't know if it was the oil or the cleaning or both feel free to test...

I think there are no gears or clutch inside because of the very clear magnet fixation you can feel while turning it slowly with your hand. That's definitely a good thing for robustness.

I did manage to remove three screws but all i got was a an enclosed metal cylinder and 3x wires connected. I still dumb founded on how to open the cylinder motor as i don't see any screw enclose it. This is on PRO model. I knew the motor inside is still spinning when i stop the bike/ brake abruptly to a halt (stop) but the motor can be heard spinning and i felt the internal clutch is not engaging it fully while the outer roller not moving at all. I have to unplug the battery to turn it off. ** Qiroll engineer support please take note of that.