TSZD2B clutch failure. Any tips on replacement?

harrys

Esteemed Pedelecer
Dec 1, 2016
351
93
73
Chicago, USA
My wife said her TSDZ2B pedals were slipping intermittently. I tried turning the pedal by hand. Sure enough, it's slipping and I can spin the pedals freely by hand w/o the chain/crank moving. What a POS motor.

That's a clutch fail. I watched the Tong Sheng video.


Guess I need to rig a crank gear puller. They don't talk about putting the new bearing into the crank. It seems I have to buy the bearing and press it in?

Anyone done this?
 
Last edited:

harrys

Esteemed Pedelecer
Dec 1, 2016
351
93
73
Chicago, USA
I recall reading a post where someone pressed the bearing out of a TSDZ2B gear and a million bearings and springs flew out, so I will buy the whole assembly, It also appears to be only sold as a complete assembly,

Now to decide if I want to get it from pswpower or someone else.
 

Sturmey

Esteemed Pedelecer
Jan 26, 2018
632
345
68
Ireland
I recall reading a post where someone pressed the bearing out of a TSDZ2B gear and a million bearings and springs flew out, so I will buy the whole assembly, It also appears to be only sold as a complete assembly,

Now to decide if I want to get it from pswpower or someone else.
I wonder if giving the clutch a good flushing with petrol and then light 3 in one oil would cure the problem as those little bearings and springs could be sticking due to solidified grease or whatever.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,882
8,517
61
West Sx RH
Rather then use petrol one could try the Alfine 8 tip when or if the factory grease is thick or sticking.
With the Alfine 8 one would have to dismantle the drive to nearly all it's component parts to get at the hard to get plces where the grease can't be got at, instead the whole drive uni is put into a empty cut down 2ltr fizzy drink bottle and then covered in ATF fluid for a couple of hours to soften the older grease. It is then left overnight to drip dry before being reitted.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
351
93
73
Chicago, USA
Here's what's going on. Definitely a quirky bearing. .All I have is brake cleaner and penetrating oil. Guess it can't hurt to try a squirt.

When I get the new gear, I will see if I can anchor it above the old rear with five extra long bolts. Then a threaded rod with a washer should make it into a gear puller.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
351
93
73
Chicago, USA
The gear is scheduled to arrive at end of the month. I tried cleaning the old gear. It was easy to remove by hand. No puller needed, Remove pedal and crank gear. Motor cover held by four small screws. Remove circlips (I had a tool), The big gear lifts off.
Big Gear.jpg

The gear has two clutch bearings in it. When the motor engages the outer gear ring, the outer bearing rotates the middle piece that is screwed to the crank gear.

The inner bearing is probably the same one used on the TSDZ2. It lets the pedals turn the middle piece attached to the crank gear.

I probably didn't have to lift the gear out. When I sprayed it with penetrating oil, i found it had gone thru the inner bearing to the other side anyway, However, with the gear out, I gave it a good shot of oil, Wiped off the excess oil, grease the outer gear and reassembled.

So far so good. Didn't slip when I rode the bike w/o power, A 22 mile ride was next, and my wife reported no slipping at all.

Hopefully, it stays "fixed", but I will have the new gear in November it starts slipping again.
 
  • Like
  • Informative
Reactions: Nealh and Woosh

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,882
8,517
61
West Sx RH
Thanks for posting harrys , might be of use for those of us running the Tongsheng.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
351
93
73
Chicago, USA
140 miles so far ..7 rides.. and the bearing is not slipping.

I am thinking there might be two ways it can slip. The first is when the sprags, which are little little wedges, get worn out so they won't jam against the bearing. The other is when they get stuck in the slipping position maybe because of bad lube. Hoping that was our problem.