The new TSDZ2(B) variant

[Dragos]

Hi,

just got a new motor from pswpower and opened it to do all the mods I have done on my first purchased TSDZ2 (older version, where the main gear had only one one-way bearing).

This motor has the 05/2022 date printed on the controller's label.

In a first step, I wanted to open up the motor and add thermal paste around it, but seem like the motor is just glued now, with what appear to be some soft silicone glue (see the picture).



Any idea why they did that? I don't think that stuff there have anything to do with heat transfer.

Overall, the motor seem more noisy that the old one (I least I think it is).

The older one did not have a throttle, this one does. I did run it from the throttle at "maximum" power (my bluetooth BMS did show around 80W drawn from the battery (48V battery), for a few minutes. It got very warm to the touch at the end (external case - not internal motor), did not expect this as it was without any load.

I will dismantle the entire motor, to change the lubrication with something that I think is better and do other mods too. I have done this for the older motor (just after purchase and before use) and I had no problems for 1500 Km on steep trails.

 

[Yanis]

I have the same glue on the motor of my TSDZ2 (non B version, bought in May 2022) around the laminations and on top of the motor screws. Maybe they did this to prevent the screws from moving due to vibrations.

I removed the glue on the laminations with a blade so I could do the heat mod with curved aluminium shims around the motor.
This motor is a lot more quiet than the previous I had : I can only (barely) hear it at high rpm. Noise wise, it seems to be a bit of a lottery with theses motors, due to large tolerances.

I read someone saying he got his motor much more quiet by changing the bearing around the tip of the motor shaft. The pitch of the sound can help you guessing where the noise comes from : a high pitch means it's a fast moving part, like the motor shaft or the blue gear, and a low pitch would more likely come from the main gear.

It's weird indeed that you get so much heat just from 80W. I don't have a throttle (have the temperature sensor instead) so I can't repeat your test to check this.

 

[Yanis]

By the way, since you have both variants of the motor, could you tell the difference when pedalling without motor assist ?
I've read contradicting things about it. I like the quietness of my (non B) TSDZ2, but without motor assistance it really feels like pedalling in the sand..

 

[Dragos]

I did not manage to mount it to the bike yet. I just wanted to do some modifications first: use my own grease, add some thermal paste for better heat transfer, get rid of the two small circlips (left & right side) and add 3 more bearings onto the axle (one in the spider and two on the left side). I managed to do all this, mounted it back and the motor still works

Being a bit subjective here , I think there is more resistance trying to turn the cranks with the motor in my hands than with the old motor.

Once I will get it mounted on the bike (no idea when I'll get some free time), I will be able to tell if there are any true observable differences.

But what I did see by dismantling and putting the motor back again:

- the main gear has the two clutches and they are custom made form what I saw. If any of the two gets damaged, the entire big gear need to be changed and I think this will be more expensive on the repair side. Instead of just replacing a single one-way bearing, the entire main gear would need to be replaced;

- now the main gear has three rotating parts instead of two, so there could be more play in them. I say it could be because there seem to be better tolerances in them, at least for now. Need to see how they wear over time. With the extra bearing mounted in the spider I can see some left-to-right play but it is very small, time will tell;

- the blue gear is gone, there is a white gear now. This white gear is pressed onto the axle of the pinion gear that drives the main gear. I don't think it's possible to replace the bearing of the pinion gear (the one between the white gear and the crown) or the white gear in itself. You'll need to buy the white gear + bearing + the pinion as a whole, making it again more expensive to repair;

- the mounting tolerances of the motor itself seem to be good, there is still some place between the base of the motor and the case where the motor attaches with the #4 screws, underneath the motor. I measured to be at about 1mm. I know the old model I have has little over 1.5mm. Back then I managed to get a small plate cut from 1.5mm copper sheet and also added some thermal paste for better heat transfer. For the new motor I have used 1mm thick thermal pads + some thermal paste on one side, to make sure it fills all the space

 

[Dragos]

I read someone saying he got his motor much more quiet by changing the bearing around the tip of the motor shaft. The pitch of the sound can help you guessing where the noise comes from : a high pitch means it's a fast moving part, like the motor shaft or the blue gear, and a low pitch would more likely come from the main gear.

My motor makes what seem like allot of high pitch noise but only on high rpm (I suppose could be from where you say) but also some low speed noise that seem to have the frequency of the main gear rotation. I think the low pitch noise came from the sprag clutch area :wink: because when I opened the motor to change the factory grease I did not find any rubbing area or something like that.