Hi. I have a mxus xf15R (rear freewheel) and they are a little noisy I think by design. They use a 5:1 straight cut planetary gears which I think are by design noisy compared to helical gears. Other than that, its a good motor. There are other complaints on line about this if you google 'mxus xf15 noisy' e.g. below. But of course, there could also be an electrical problem in your case making matters worst. (e.g. poor phase connection will cause the motor to go out of balance/noisy)
PS One of my bike has steel mudguards that resonate every now and again when the motor is under load at a certain pitch and are noisy. I also had a spoke nipple that came loose lately and fell into the wheel cavity, making a lot of noise.
Hello, I just installed a MXUS XF15 front hub motor on my cargobike, and it is working really well, except that it makes a lot of noise. On my normal ebike I have a Cute Q100h and you can barely hear that motor above the road noise. With the cargobike I can hear it even when listening to music...
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