Toseven DM02 motor whine

[jeffieh]

My DM02 (approx 1000km on the clock) had started whining under power. Only under power.
You can hear it clearly in the last couple of seconds of the clip.
Guess I'll have to tear it down but I wonder if anyone's familiar with that sound from their mid-drive?
Many thanks in advance,

Jeff

 

[dgc]

My first thought was to check that the main gear and pinion has enough grease on it, then go thro' the other gears, you may pick up something with just a visual check, say if any gear was shredding, have you seen this?

 

[dgc]

Tempted fate here, my e-bike with the TSDZ2B drive has started slipping when under load, but before anything else I will have to check the cassette is not slipping or the chain is not riding over the teeth on the cassette due to miss alignment, so just done a slight adjustment on the derailleur. Will ride out tomorrow. But would just pull out the main gear if it came to it.

 

[jeffieh]

My first thought was to check that the main gear and pinion has enough grease on it, then go thro' the other gears, you may pick up something with just a visual check, say if any gear was shredding, have you seen this?

I guess I could try more grease. That vid is very useful, thanks.

 

[jeffieh]

UPDATE: Stripped it down today, and it turned out to be two small bearings on the 'motor' side: the one below the blue gear, and the other on the end of the motor spindle. Water damage! Easy fix, but I'll be looking very carefully for where the water got in when I reassemble it.

 

[jeffieh]

Tempted fate here, my e-bike with the TSDZ2B drive has started slipping when under load, but before anything else I will have to check the cassette is not slipping or the chain is not riding over the teeth on the cassette due to miss alignment, so just done a slight adjustment on the derailleur. Will ride out tomorrow. But would just pull out the main gear if it came to it.

I used to have a TSDZ2 (until it was stolen), and I discovered you can fix a slipping sprag clutch by cleaning it in solvent & regreasing (in my case a couple of the pawls had gotten stuck with gooey grease and weren't catching). Just watch out for the torque sensor behind the main gear - they're very delicate.

 

[dgc]

jeffieh, Thanks for info, I may be lucky, readjusted the derailleur and we may be OK, yes have changed the main gear assembly on a TSDZ2 before, used the chain-wheel spider, long screws and packers to pull the main gear off.
Glad you sorted it out, these mid-drives seem to have a water infliction.

 

[Hardingen]

Hi. I have gotten some chainring play after not very much usage. A lot of hills and I`m not featherweight, but still...So thinking it got to be the bearing in the picture. Does anyone know the specs of this ? I know it`s 30 mm outside. Toseven responds quickly, but the answers are a mixed bag. I don`t think they believe I tie my one shoes.

 

[Hardingen]

.....own shoes....damn

 

[dgc]

OK, can you slide it off the shaft and just measure the OD which you say is 30mm, then the ID and the width of the bearing, if you are lucky it may have the size marked on the bearing outer track edge. BUT I could be wrong 30mm OD seems a bit big considering drive has to fit thro' a standard BB.

For example only, it could be a 61903 which is 30mm OD x 17mm ID x 7mm Wide, where as on the TDZS2's for the third bearing mod a 61902 bearing is used which is 28mm OD x 15mm ID x 7mm Wide

 

[Hardingen]

The outer diameter I saw in the YouTube video. Was hoping to get the specs and buy a bearing before dismantling the motor. And that bearing is on the right and doesn't go trough the frame. But 6903 is the one, it looks like, when looking at the standards.

 

[dgc]

OK then, 61903-2RS (6903 2RS) Deep Grooved Ball Bearing / Thin Section Bearing take the 2RS off if it's not a sealed bearing or 1RS if it is has a single seal.
The only reason for thinking the bearing was 28mm OD was because the retaining / locking ring thread inner diameter is around 32mm on the TSDZ2(B) so assuming the DM02 would not be a lot different, anyway learn something new everyday.

 

[dgc]

Just watching a YouTube video comparing the DM02 and the TSDZ2B where a vernier was put across the DM02 axle which measured around 16.95mm dia so as you said it's a 61903 (6903) Deep Grooved Ball Bearing which is 7mm wide.