Cromotor Ticking/Clicking Sound on eBrake

[Merlin]

Hey,
is the "Clicking" Sound normal when i switch from Accelerate to eBrake?

Dont look at the shaky video. was not easy to push a button and give throttle. Just hear the "sound".
it happens only once on switching from Accelerate to Brake.

when you brake - it clicks once.....
tapping ebrake again no click sound

same on accelerate....

sounds like there is some play "inside" the motor? but where?!

[youtube]vuVWw4Al8wo[/youtube]

 

[amberwolf]

I can't see the vid (low wifi bandwidth) but is it possible the axles are rocking in the dropouts? That could click if it's rocking hard enough to hit the flats on the dropouts in each direction, and it wouldn't click a second time until it's been rotated the opposite direction by the force of the opposite power application.

 

[Holocene]

is the "Clicking" Sound normal when i switch from Accelerate to eBrake?

Hi Merlin,

That 'ticking' noise sounds like a spoke to me... Perhaps check for loose/broken spokes? Good luck!

Cheers,
Holocene

 

[Merlin]

I can't see the vid (low wifi bandwidth) but is it possible the axles are rocking in the dropouts? That could click if it's rocking hard enough to hit the flats on the dropouts in each direction, and it wouldn't click a second time until it's been rotated the opposite direction by the force of the opposite power application.

i will check it out.
its a raptor with clamped dropouts i dont think so. but who knows.
i have the beast on my table now and proof every screw.


also i will check every single spoke.

thx

 

[bionicdan]

isnt it a keywayed stator? That would make a lovely click each time you demand opposite force direction. My mac one isnt a tight fit and sometimes creaks on engaging. Put some tape down it or some thin alloy to see if it stops or dulls it. Then maybe look at getting a new or bigger key.

Sounds too clear though. A magnet shifting would make a good clank
http://endless-sphere.com/forums/viewtopic.php?f=2&t=60781&hilit=loose+magnet

Using search terms cromotor-loose-magnet seems to be a few people with that problem. There is a .5mm gap in the magnets when they are all fitted and some peoples had a shim to keep it solid and some didnt. It looks like the guy above "offroader" eventually had every single magnet spin backwards as fast as the wheel went forward doh. He didnt have a shim

 

[Merlin]

on weekend i looked at everything.
all spokes are okay. every screws are tighten. (brake/sidercovers/freewheel/disc)
dropout axle was hard clamped. the sound is still there. not loud as i had before...but still there.

put some tape down? what did you mean?

 

[cal3thousand]

Do you get the sound running the motor with the wheel in the air?

 

[bionicdan]

Look at your stator. It has a keyway. You need to open your motor. No amount of forum talk or guessing will help lol

 

[Merlin]

Do you get the sound running the motor with the wheel in the air?

i will try it. but pressing the button to start regen only stops the wheel immediately.
what would it tell me when the sound is still there?



ah now i understand what a keyway is.
sure, when theres some play the sound would fit.
mhhh...iam not sure that i have all tools to open the cro.

 

[Spicerack]

I would look at the loose magnet too as mentioned above. Been a recent case of it.

Good luck!

 

[Merlin]

hey spicerack,
but when it was a lose magnet, why it just clicks only once in a direction?

i ask vladimir from zelena and he told me theres nothing inside what can make a sound like that....and WHEN, the motor is broken and i cant drive.

we have so much selled cromotors here, but it seems no one has that sounds like me.

 

[peters]

Sound is at braking only, but not at acceleration?
Maybe it could help to locate the source of the sound if put the bike on a stand, press the ebrake (or short the motor wires after disconnecting from the controller), grab the tire and rotate the wheel forward and backward firmly. Or just accelerate and brake while the bike is on the stand.

 

[Merlin]

nope its on ebraking and accelerating.

not easy to fix that monster in place to rotate firmly the wheel. But i will try it. thx.

 

[Spicerack]

Viel Glück! Have a look at this recent post:

http://endless-sphere.com/forums/viewtopic.php?f=2&t=60781

 

[bionicdan]

hey spicerack,
but when it was a lose magnet, why it just clicks only once in a direction?

Im guessing the magnets are NS-NS-NS-NS (NORTH SOUTH)

So if one has 0.5mm of a gap, as some people suggest can happen in a cromo, then one loose magnet would swap from one side to the other which each change in direction.

Imagine 3 magnets. Two are glued to the walls of a box. The third is stuck to the left. With a big electromagnet you could force the middle magnet to fly to the right and back depending on which way you point your electromagnet.

 

[Merlin]

a little update:

the sound is 3 times louder when motor is on temp (80-90°)
when i start in the morning. the sound is very low. so low i would live with it.

looks like the keyway stator/axle can be the Problem. Stator heats up and axle becomes more play

 

[peters]

I can confirm I have the same problem with Cromotor v2.
Not this loud, but there is a small hit when changing between acceleration and regen. Not depends on temperature at mine. Really looks like the axle turns a little bit in the aluminium stator. There is no clamping in any motor, just the keyway, and the gap may increase by time, I guess. Solution can be to press out the axle and glue in with strong epoxy (I will try this), or not using regen...

 

[Tench]

I don't think it is the stator, the sound would be duller, this one rings like it is resonating through the spokes. I think the loose magnet with a little room to move is a distinct possibility. You cant rule anything out or do an accurate diagnosis, it is going to need exploring.

 

[Merlin]

will Rebuild my Wheel with MX Rim and 9g Spokes.
we will see if it was some Spokes.
But why comes it louder when the motor heats up?

i have opened the Motor. I cant see any lose Magnets at all.
now i have unlaced my cro.
in the meantime i have a 3540 on the rear.......duhhhhhh 2 minutes and it is up to 140° ;(

 

[crea2k]

Can you turn down the regen current on your controller ?, if so turn it down a bit so it still moves and then try it.

Do you get the sound running the motor with the wheel in the air?

i will try it. but pressing the button to start regen only stops the wheel immediately.
what would it tell me when the sound is still there?



ah now i understand what a keyway is.
sure, when theres some play the sound would fit.
mhhh...iam not sure that i have all tools to open the cro.

 

[Merlin]

i did...the sound is still there. you need just 1% Throttle to get "the click"
and also just 10a regen it clicks also.

atm i have a 3540 hubbie on the rear. same rim, same spokes.
absolutley no sound on load change.

 

[crea2k]

Its not the brake disk catching is it ?. I would remove the caliper just to be sure.

 

[Merlin]

i dont touch the brake. no scratching sound from caliper.
just push the regen button.
but freakin out....just to be sure, i will do it

 

[Karolis]

I am also having this problem. And It was from the start i putted that motor on bike. First I thought it was my torque arm. But it sits tight as hell. Then I thought it was axel. I made a bigger keyway, pressed axel back. But that didn't helped. I am also having other sounds. Then i lift a cold motor for a spin, it is spinng quite and nice. But if the motor warms up a little bit. It is periodically hitting something in motor. Another sound is so dam loud cracking noise that first i thought my suspension was broken. It sounds like metal cracking. It is also happening everytime only in first moments of acceleration and regen. And now i think for all those sounds responsable magnets.

 

[John in CR]

That didn't sound like inside the motor to me, so either a spoke (didn't sound like one) or my #1 the motor axle rocking in the dropouts/torque arms. If they aren't clamping type, then that's surely what it is. Non-clamping I don't care how tight you think they are will always have play with significant power and regen. Even clamping type can get just enough play to make a similar noise and can need extra tightening.

Make sure it's off, short the motor phase wires together and get the wheel off the ground. Then you can move the wheel back and forth by hand to reproduce the changing direction loads and get to the bottom of it safely getting your ears close to the source.