Mxus 3k V3 - Clicking / clunk sound when changing direction. (regen/throttle)

[Jimmydoerty]

Hi there all,

I've been running my mxus 3k for about 8 months now everythings been good. 1-3kw average riding, 5kw peaks. Never has gotten hot.

Suddenly today, whenever I engage the regen brake I hear and feel an audible clunk / thud through the pedals / frame. Then when I start throttle again I hear the same clunk.

It only seems to happen when switching between regen / throttle. If I unplug regen brake sensor, I can ride normally with no sounds (avoiding regen). But when the wheel "changes direction" from regen brake/throttle I get that clunk, almost like the rotor or stator is loose or something and has slack before it engages.

Video above of the sound. I have no idea what causes this, it started after I removed then reinstalled my wheel to adjust my chain and cassette, but everything seems 100% tight and seated properly.

Many thanks for any tips!

 

[E-HP]

Are your torque arms tight?

 

[Jimmydoerty]

Are your torque arms tight?

Afternoon E-HP,

They seem to be tight enough yes, I did try re-tightening the clamps on my arms + cranking down more on wheel nuts - maybe too tight?? It happens even at very low speeds / low torque situation. They should def be tight enough to withstand any slack in the axle seat, of which I dont think there is much anyway... tried to give it a good shake and twist - no obvious movements

Many thanks!

 

[fechter]

Possibly the motor stator came loose from the axle.

 

[Jimmydoerty]

Possibly the motor stator came loose from the axle.

Thanks folks!

I will wait for the reply from Mxus support, and then I think I will have to open this thing up to really find out!

Wish me luck people!!!

 

[amberwolf]

I've broken axles on those. Maybe one of your axles is actually broken just inboard of the dropouts.

If there is any play *at all* in the axle-securing hardware, including any slack in the holes the axle fits thru, the axle *will* rotate in them every time torque is appplied in either direction. Everytime that happens, it will damage the holes (or the axles) and be able to move a little more. If it can only move in one side's holes, then the other side's axle that's held securely will be twisted at it's root, and stressed, and can shear thru and break off.

 

[derekderek]

turn it upside-down and run it. you may see something when you hit the brakes. brace it well. i fired up a new-to-me direct drive motor while sitting on a stool next to it. it fired up in reverse, jumped into my lap, and i was sitting there with the pedals and sprockets tearing up my hands.

 

[derekderek]

also possible it is rear brake disc or caliper. something else to look for while it is running upside down. good luck. just remember. whenever you do something and something else goes wrong, you just did it! go back over everything you did. if you haven't had one of these hubs apart yet, youtube...