this was a diy kit sold by ebikling. they claim it is a 4kw direct drive hub motor.
i am using 66.6 44ah lipo back and a controller that can push 120amps, but normally i dont exceed 3kw.
i built this to commute about 60 miles a day at about 30-35mph
i built this bike about a year ago and love it, but it has developed a noise coming from the motor.
the noise seems to be really bad at low speeds and high torque situations. but the noise is almost always there and there is a pattern to it, the noise peaks in sync of the rpm of the motor. the noise is like a ticking sound at first, then it seems to turn into a tapping noise, and if i am really heavy on the throttle it becomes a squeaking noise. but sometimes it also seems to make a weird grinding rattling noise, i cant tell if this is my motor, or the luggage rack shacking from the pulses of the motor. some times it almost sounds like my rotor is tapping the brake pads, but i have disconnect the rear cable and the noise persists, and again, its mostly under medium to high throttle where i notice it the most. when its the loudest i can let off the throttle just a bit and it mostly goes away at high speed, but at low speed it sounds like something is about to fall part.
the entire time i hear this noise i cant say i have noticed a loss of power
i suspect heat is an issue, i have tried to remedy this with devices that can read the temp sensor signal values but thats another story and hasnt worked out and i plan to do the statoraid thing.
i suspect between my speed, the weight of the bike, and the 40lbs of battery sittings towards the back of the bike, and the long commutes that i have likely damaged the bearings, plus i weigh about 220lbs.
i have had this motor open several times, my magnets came loose, but i used a high temp epoxy and havnt had that issue again, and i have had to replace all six hall sensors a few times and finally bought better sensors and havent had an issue since.
i suspect the axel is a tiny bit bent and always has been, i think damaged from shipping, so maybe a tiny wobble also contributed to the bearings getting worn out? the wobble from the bent axel is very hard to spot, but i can see it my rear freewheel.
i have had the bearings out and they feel silky smooth to my touch, but the bearings are always room temp by the time i get to them.
if it is the bearings, can anyone recommend a source for them?
incase it matters: i have a dso, and i can see the square wave of the hall sensors and they look good on one side, the other side is noisy for some reason, i was told it was from my rotor cutting into the hall wires and i just soldered them back and wrapped it with tape. my motor has two sets of hall sensors, i assume if one goes sensor goes bad, you just switch to the other side.
i also have been breaking spokes, but recently bought good spokes and a tool to make sure they are all the same tension, but i am still new to this and sometimes wonder if i dont have them tight enough which may cause a rattle, but they should not squeak like the noise can make if i ride it harder than average, so i kinda doubt this is the noise, but could be part of the noise
i guess i am hoping someone can say that it sounds like cheap bearing failure, from heat, weight etc etc.
if it is the bearings, can anyone recommend a source for them?
appreciate any input
i am using 66.6 44ah lipo back and a controller that can push 120amps, but normally i dont exceed 3kw.
i built this to commute about 60 miles a day at about 30-35mph
i built this bike about a year ago and love it, but it has developed a noise coming from the motor.
the noise seems to be really bad at low speeds and high torque situations. but the noise is almost always there and there is a pattern to it, the noise peaks in sync of the rpm of the motor. the noise is like a ticking sound at first, then it seems to turn into a tapping noise, and if i am really heavy on the throttle it becomes a squeaking noise. but sometimes it also seems to make a weird grinding rattling noise, i cant tell if this is my motor, or the luggage rack shacking from the pulses of the motor. some times it almost sounds like my rotor is tapping the brake pads, but i have disconnect the rear cable and the noise persists, and again, its mostly under medium to high throttle where i notice it the most. when its the loudest i can let off the throttle just a bit and it mostly goes away at high speed, but at low speed it sounds like something is about to fall part.
the entire time i hear this noise i cant say i have noticed a loss of power
i suspect heat is an issue, i have tried to remedy this with devices that can read the temp sensor signal values but thats another story and hasnt worked out and i plan to do the statoraid thing.
i suspect between my speed, the weight of the bike, and the 40lbs of battery sittings towards the back of the bike, and the long commutes that i have likely damaged the bearings, plus i weigh about 220lbs.
i have had this motor open several times, my magnets came loose, but i used a high temp epoxy and havnt had that issue again, and i have had to replace all six hall sensors a few times and finally bought better sensors and havent had an issue since.
i suspect the axel is a tiny bit bent and always has been, i think damaged from shipping, so maybe a tiny wobble also contributed to the bearings getting worn out? the wobble from the bent axel is very hard to spot, but i can see it my rear freewheel.
i have had the bearings out and they feel silky smooth to my touch, but the bearings are always room temp by the time i get to them.
if it is the bearings, can anyone recommend a source for them?
incase it matters: i have a dso, and i can see the square wave of the hall sensors and they look good on one side, the other side is noisy for some reason, i was told it was from my rotor cutting into the hall wires and i just soldered them back and wrapped it with tape. my motor has two sets of hall sensors, i assume if one goes sensor goes bad, you just switch to the other side.
i also have been breaking spokes, but recently bought good spokes and a tool to make sure they are all the same tension, but i am still new to this and sometimes wonder if i dont have them tight enough which may cause a rattle, but they should not squeak like the noise can make if i ride it harder than average, so i kinda doubt this is the noise, but could be part of the noise
i guess i am hoping someone can say that it sounds like cheap bearing failure, from heat, weight etc etc.
if it is the bearings, can anyone recommend a source for them?
appreciate any input
