Third Tongsheng TSDZ2 installation. Too much assist for too much of the time!?

Sailorbass

Pedelecer
Nov 30, 2020
46
4
Hi Folks, I did have my Tongsheng TSDZ2 up for sale, but I've kept it and installed it on a new mountain bike. I bought a nearly new Forme Curbar 2 locally for next to nothing, and put the motor on. Third time I've installed this motor. Key learning points:

1. Internal cable routing that emerged by the bottom bracket proved to be a pain, and I had to re-route the rear brake hose externally, just managing to tuck it behind the motor bottom bracket lock ring. It was a very tight fit, however.

2. On previous installations, I removed the front derailleur because it's not needed. On this bike, the cable is routed internally, and I really didn't want to pull it out in case it was needed in the future. I re-positioned the derailleur on the down tube, unhooked the cable and moved the handlebar shifter so it was out of the way.

3. Existing chain only just long enough to go round motor chain ring, which is bigger than either of the two rings I took off the bike. See rear derailleur position in photo.

4. Re-positioned front derailleur got in the way of fixing the rear mudguard. Had to cut a hole in the mudguard so it fitted over/around front derailleur.

5. Must remember to check and tighten all motor anchor bolts after a few rides. With the two previous installations, the motor bolts came loose after four rides.

6. As before, I didn't fit the speed sensor. Shakedown ride showed everything working well. It did feel that I was getting a lot of assist a lot of the time. With two bars showing, I was flying along. With three and four bars, it didn't feel like I was getting appreciably more assist, even when going up still hills and pressing hard on the pedals. Sort of all-or-nothing. I've been considering a thumb throttle - would this simply replace the handlebar mini-switch that plugs into the VLCD5 display?

Forme ebike.jpg
 

TJS109

Pedelecer
Sep 29, 2017
112
48
77
Glos
It will only work with the correct controller/motor. Has to be the one with the 8 pin display lead.
Probably a good idea to fit a brake sensor as well for safety reasons. Plugs in as above.
 

Sailorbass

Pedelecer
Nov 30, 2020
46
4
Thinking about it, and reading others' posts about throttles, I don't think this will cure my problem. If I select the lowest level of assist, the bike feels very fast and perky. The motor cuts out when I stop pedalling, but kicks straight back in again the moment I start pedalling, even if I'm gently coasting/pedalling down hill. Selecting any higher level of assist when going uphill doesn't seem to make that much difference. It's almost as if the bike is permanently in a high level of assist. I have not fitted the speed sensor (because I bent the fiddly-tiddly pins the first time I tried...) Any thoughts, folks?
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
3,850
2,763
Winchester
What kind of controller does it have. It sounds like a pure speed controller; that gives maximum assist whenever it gives any assist, and the difference of assist levels just changes the speed at which the assistance stops.

Whatever kind of controller it could be that not fitting the speed sensor has deprived the controller of important input to needed to give the most appropriate power.
 

Sailorbass

Pedelecer
Nov 30, 2020
46
4
The whole kit worked perfectly on a previous mountain bike without the speed sensor. All I've done is transferred everything to a new bike.
Battery downtube plate.jpgBattery label.jpgUnderneath battery.jpg
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,981
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West Sx RH

Sturmey

Esteemed Pedelecer
Jan 26, 2018
648
354
68
Ireland
Thinking about it, and reading others' posts about throttles, I don't think this will cure my problem. If I select the lowest level of assist, the bike feels very fast and perky. The motor cuts out when I stop pedalling, but kicks straight back in again the moment I start pedalling, even if I'm gently coasting/pedalling down hill. Selecting any higher level of assist when going uphill doesn't seem to make that much difference. It's almost as if the bike is permanently in a high level of assist. I have not fitted the speed sensor (because I bent the fiddly-tiddly pins the first time I tried...) Any thoughts, folks?
Two things I would suspect.
1. Recheck the 8 pin connector as there may be problems on tx or rx wires. Make sure no bent pins and connector is fully in. Also make sure there is no shorts /contacts at the damaged speed sensor connector.
2. It is possible to damage the calibration of the torque sensor hall sensor which is in the center of the spindle. (I hope you did not use a hammer!) I believe it is possible to check this using the vlcd-5 hidden menu but I have never needed to do this. Others may be able to help you here. The instructions I believe are........
Hidden menu Vlcd5:
Press the Info and the Power buttons simultaneously for 10 seconds under ODO menu, then press only the Info button to show “ODO”, “TRIP”, “AVG”, “TIME” , “TE” (torque value) and “TE1” (initial torque value) respectively and circularly.
Under submenu “TE” or „TE1“, press Info again to show the torque value, which is for service inspection use only. 46275
 
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Sailorbass

Pedelecer
Nov 30, 2020
46
4
Yesterday, having transferred the Tongsheng to my new bike, I checked the configuration of the VLCD5 LCD display. I got to the power setting - I think it's setting number 6 - and had no idea what value to set it at. Default appears to be 16. Would changing this alter the power/assist delivery characteristics of the set up? If not 16, then what would be a sensible alternative value to try?
 

Sturmey

Esteemed Pedelecer
Jan 26, 2018
648
354
68
Ireland
Yesterday, having transferred the Tongsheng to my new bike, I checked the configuration of the VLCD5 LCD display. I got to the power setting - I think it's setting number 6 - and had no idea what value to set it at. Default appears to be 16. Would changing this alter the power/assist delivery characteristics of the set up? If not 16, then what would be a sensible alternative value to try?
That setting makes no difference in my case. It has been reported that on older units it worked but was deliberately locked in the more recent controller (but not in the vlcd5) to prevent users from turning up the power excessively as this resulted in warranty claims.
 

Sailorbass

Pedelecer
Nov 30, 2020
46
4
BINGO!! Ha! Following @Sturmey's advice, I checked the 6-pin connector between the motor and the battery, and found a bent pin. Some tweezers and a some swearing straightened it out, and I very carefully pushed the connector back together, making sure it went home all the way. Quick test ride round the block - 4 very clear levels of assist! So - it's the old Steve (me) problem - ham-fisted with those flaming tiny little pins. This time, I've made sure that the connector is outside of the frame geometry so I can remove the kit without having to split the connector. Most grateful - thank you, Sturmey.