Offroader wrote:I would like to give an update about the hubmotor noise. When I remove the axle nuts the noise goes away. When I tighten the axle nuts back on the noise returns. I still have the motor inside the dropouts.
Any ideas on why this would happen? Is this like what Merlin said about motor resonating through the swing arm?
Just odd how it would not do this still with the motor still in the dropouts, I would think it would still resonate as it is still making decent contact with just the axle nuts loosened. But the noise really does go away once loosened.
Any way to fix this?
My guess would be that the noise is still there when the axle nuts are removed, you can just not hear the resonance.
Think of a guitar, vibrations and resonances are planted from the string to the body, wood etc. The tighter the strings are the higher the pitch.
Something similar might cause the noise you hear when you tighten the axle nuts. When tightened down properly the motor is now become anchored to the bike via the axle, drop outs and the nuts secure the connection. Any vibrations, resonances etc can now travel freely up the swing arm, where swing works like the body of the guitar or much like a tuning fork, amplifying the sound. And that is why madin(iirc) discovered sound deafening material inside swing arm helped.