Elephant bike conversion

lotusndy

Finding my (electric) wheels
Aug 18, 2017
8
4
60
canterbury kent uk
I have an ex Royal mail post bike that I bought from Elephant bikes that I fancy adding a mid drive to, a forum search has turned up a few people that may have also done this, any one able to offer any info on how it was done?

thanks Andy
 

D C

Esteemed Pedelecer
Apr 25, 2013
1,140
575
I have an ex Royal mail post bike that I bought from Elephant bikes that I fancy adding a mid drive to, a forum search has turned up a few people that may have also done this, any one able to offer any info on how it was done?

thanks Andy
I haven't done this and sorry can't advise but I think it's great that you are doing this, an iconic bike.:)
Dave.
 

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
Hi,

I am looking at doing this and am interested in how you managed to fit the anti rotation bracket with the kickstand in place. I have a tsdz2 on another bike and know from bitter experience the problems that arise from not using the bracket.
Any hints welcome

Thanks

Tim
 

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
It is part of the kit. The torque produced will turn the motor in the frame if not fixed properly. Bafang seem to manage to have a system that allows a tight fit on the frame and will not rotate. The tsdz2 system does not seem to be as good and will loosen if the bracket is not employed, at least when I installed one

Tim
 

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
Andy,

Thanks I thought so from the photograph.
Guess I will wait till the bike arrives and see what is possible. The kickstand looks so useful I would really like to keep it.

Tim
 

lotusndy

Finding my (electric) wheels
Aug 18, 2017
8
4
60
canterbury kent uk
The kickstand is useful as the bike weighs a ton!, I was was just too impatient to get it electrified to figure a way to retain it, let me know how you get on.
 

Fizz

Finding my (electric) wheels
Apr 30, 2019
21
1
Will do, but will be a few weeks yet, last resort will be to use the Bafang instead.
I am hoping to convert my elephant bike when it arrives. I can’t find a bike that does everything I want cargo-wise on budget so this looks like a good option. I need to keep the rear rack free though - did you mount the battery there as Lotusndy did or is it possible to fit it to the frame somehow? Also, I definitely need to retain the kickstand... Many thanks!
 

Woosh

Trade Member
May 19, 2012
19,477
16,423
Southend on Sea
wooshbikes.co.uk
if you want to keep the kickstand, then go for a BBS01B .
 

lotusndy

Finding my (electric) wheels
Aug 18, 2017
8
4
60
canterbury kent uk
I am hoping to convert my elephant bike when it arrives. I can’t find a bike that does everything I want cargo-wise on budget so this looks like a good option. I need to keep the rear rack free though - did you mount the battery there as Lotusndy did or is it possible to fit it to the frame somehow? Also, I definitely need to retain the kickstand... Many thanks!
I mounted the battery on the rear rack as I didn't need it and I had a battery pack already, you might be able to use a water bottle style battery though..
 
  • Like
Reactions: Fizz

chris667

Pedelecer
Apr 7, 2009
164
108
One year on and the bike is complete and running beautifully.
Elephant bike with TSZD2 mid drive motor with 10Ah battery pack, giving about 40 mile range.
Can go into more detail if anyone is interested,

Sorry to hijack this thread, but I would love to hear about your conversion. This might be a really useful thing for me.
 

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
It's been a while but I have just fitted a TSDZ2 to my elephant bike.
No problems and there is plenty of space for the anti-rotation bracket while keeping the kickstand. Works like a dream. I think I am going to try upgrading with the opensource firmware that is available we will see how that goes!
 

Attachments

  • Like
Reactions: D C

JRAB

Just Joined
May 18, 2022
2
0
It's been a while but I have just fitted a TSDZ2 to my elephant bike.
No problems and there is plenty of space for the anti-rotation bracket while keeping the kickstand. Works like a dream. I think I am going to try upgrading with the opensource firmware that is available we will see how that goes!
Hey. Those photos are great, very helpful - just what I'm looking to get to.
It's been a couple of years since you did that conversion, would you mind sharing your experience since - reliability, usability, etc?

Thanks
Richard.
 

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
Hey. Those photos are great, very helpful - just what I'm looking to get to.
It's been a couple of years since you did that conversion, would you mind sharing your experience since - reliability, usability, etc?

Thanks
Richard.
Well I have two bikes with TSDZ2s fitted.
I upgraded both to the open source firmware without any problem and this improved the performance slightly.
The one on the elephant bike experienced a torque sensor failure. However the opensource firmware allowed me to keep using it in cadence mode. For the use this bike gets, pottering into town for shopping etc, this is probably an improved operating mode.
The other unit is working fine without problems.
 

JRAB

Just Joined
May 18, 2022
2
0
Well I have two bikes with TSDZ2s fitted.
I upgraded both to the open source firmware without any problem and this improved the performance slightly.
The one on the elephant bike experienced a torque sensor failure. However the opensource firmware allowed me to keep using it in cadence mode. For the use this bike gets, pottering into town for shopping etc, this is probably an improved operating mode.
The other unit is working fine without problems.
Thanks for the reply, that's good to know.

Re: the torque sensor, I read somewhere that these are fairly easy to replace, and the later sensor is apparently a different type and more reliable? When you say "run in cadence mode" does that mean similar to the Bafang motor, where the assist comes in when pedalling is detected, and the amount of assist is not dependent on pedal effort?

I'm also interested in how you found the power assist worked with the original Pashley gear ratios? The Tongsheng apparently works best between about 70-80rpm cadence? 2nd gear on the hub is direct, so with the 42T crank & 20T sprocket an easy 75rpm cadence gives 12mph. That means top gear gives 15.9mph and bottom gear gives 9mph at the same 75rpm cadence.

Does the motor have enough torque to drive a loaded bike up a decent hill (say 7-8% gradient) at 9mph in the torque/cadence sweetspot, while still allowing cruising under power on the flat at ~15mph? Or does the gearing need tweaking to better match the torque & cadence? (Bear in mind I'm an ok club cyclist and can ride a 10-mile TT averaging around 250W (unassisted!), I just don't want to have to ride TT efforts up hills on the way back from the shops.....)

Thanks!
 
Last edited:

TJS109

Pedelecer
Sep 29, 2017
112
48
76
Glos
Thanks for the reply, that's good to know.

Re: the torque sensor, I read somewhere that these are fairly easy to replace, and the later sensor is apparently a different type and more reliable? When you say "run in cadence mode" does that mean similar to the Bafang motor, where the assist comes in when pedalling is detected, and the amount of assist is not dependent on pedal effort?

I'm also interested in how you found the power assist worked with the original Pashley gear ratios? The Tongsheng apparently works best between about 70-80rpm cadence? 2nd gear on the hub is direct, so with the 42T crank & 20T sprocket an easy 75rpm cadence gives 12mph. That means top gear gives 15.9mph and bottom gear gives 9mph at the same 75rpm cadence.

Does the motor have enough torque to drive a loaded bike up a decent hill (say 7-8% gradient) at 9mph in the torque/cadence sweetspot, while still allowing cruising under power on the flat at ~15mph? Or does the gearing need tweaking to better match the torque & cadence? (Bear in mind I'm an ok club cyclist and can ride a 10-mile TT averaging around 250W (unassisted!), I just don't want to have to ride TT efforts up hills on the way back from the shops.....)

Thanks!
Yes it works like the Bafang in cadence mode.
I used it in hybrid mode and found it powerful enough but I tend to potter about so maybe not a good test. You have to peddle quite fast to get 15MPH out of it with standard gearing, faster than I found comfortable.