TSDZ2 Alternative

[not dave]

Hello,
I bought a TSDZ2 kit last year and while the performance has been great, there have been number of issues. What alternatives to the TSDZ2 are there that I can re-use the same battery (a 48v 17.5 ah Samsung downtube battery)? I am particularly keen to get a kit with a small / discreet display.
Also, is it possible to fit the downtube battery on a rear rack? The battery seems to be too heavy for the supplied plastic mount and despite adding cable ties and rubber tubing to damp the vibrations, the mount still flexes side to side. I appreciate that moving the battery up and back will slightly affect the handling, but i am quite heavy myself (~100kg).

 

[vfr400]

You should tell us about the issues you had, which might help other forum members with their decisions. Also, it might help us make recommendations for alternatives. Was it not powerful enough, too noisy for you, too heavy, to inconvenient or what? Also, tell us what you want to do with your bike. is it commuting, cross-country, downhill racing or what?

You can put the battery where you want, but it depends what type of bike you have and what type of riding you do. When you mount the battery too high and too far back, it can make the bike's handling terrible, but tucked in low up against the seatpost, it can be quite acceptable.

Downtube batteries should have at least three fixings. Did you add an extra rivnut or are you using just the two bottle fixing screws.

 

[not dave]

Hi vfr.
issues were around reliability. A crank failed, the charger failed and now the motor has stopped working and is making a noise when I pedal and not producing any power.
Riding is all on road and general commuting / leisure riding.
Bike is a Whyte Dorset, with a rear pannier rack. I’ll take some photos in the morning.

The battery is currently only attached on the two bottle fixing screws. I’ll chat with the local bike shop to see if they can add another further up the tube.

 

[vfr400]

A hub- motor should be fine for that. At 48v, you'll have plenty of power for hill-climbing. Hub-motors are generearlly more reliable and user-friendly. I can't recommend which one without knowing what speed you want and how heavy you are.

 

[not dave]

What are they like to ride? when I was looking at kits last year mid drive motors seemed to be more recommended as they were more ‘natural’ to ride.
But... your statement that they are more reliable does get me interested...
I am about 100kg and would like to ride as quick as possible. I am in Cardiff and just a little north of me at some pretty steep hills, though only some of my rides are in that direction.

 

[vfr400]

Any of the middle-sized cassette motors would be fine for what you want. Many of us prefer the KT sinewave controller because of it's fast response and torque simulation (current control). 15 amps is about right if you like to pedal hard sometimes, or the 17A one gives 13% more power and torque and 20A a bit more still. If you want to cruise in the low 20s with steady pedalling, you should get a 36v motor with around 260 rpm or a 48v one with around 328 rpm. The 328 rpm AKM128C (Q128C or QQ128C depending on where you get it from) is my favourite. You can get them from Greenbikekit, BMSBattery or Topbikekit:

AKM-128CST 48V500W Rear Driving Hub Motor 36holes with 20/26inch/700CC wheel rim [AKM-128CS 48V500W motor 26/700cc] - $131.95 : Zen Cart!, The Art of E-commerce

Zen Cart! AKM-128CST 48V500W Rear Driving Hub Motor 36holes with 20/26inch/700CC wheel rim [AKM-128CS 48V500W motor 26/700cc] - ★★★★★ AKM-128CST 48V500W Rear Driving Hub Motor 36holes with 20/26inch/700CC wheel rim Specification: 1. Voltage: 48V 500W 2. Brake type: V-brake, rim brake and disc...

www.topbikekit.com

Put the controller in an under the saddle toolbag. Alternatively, you might be able to buy the controller that fits your battery from Topbikekit.

This system is better than a torque sensing crank-drive in that you can always pedal as hard or not hard as you want. It's just as natural: you pedal the bike and it goes. Pedal harder and it goes faster. The only difference is that you can get power without any pedal effort if you want.

IMHO, there's loads of rubbish written about crank motors. The system is fundamentally flawed in that the power has to go through the chain, and the drive train just isn't designed for that sort of torque, which means crunchy gears, rapid wear and reliability issues. With a hub-motor you get smooth power and a less frantic ride.

My Q128C and the rest of the electrical system has given me zero issues in 6 1/2 years and 6 1/2 thousand miles. I replaced the battery once.

The AKM128C normally has an easy-peel label. Without the label, the motor is more or less identical to any typical 250w one. In fact, the same motor is used in some well known mainstream 250w ebikes.

 

[not dave]

Ps, here's a short video of the noise the TSDZ2 makes when i put some pressure on the pedals. Any idea what this fault is?

 

[Sturmey]

Ps, here's a short video of the noise the TSDZ2 makes when i put some pressure on the pedals. Any idea what this fault is?

It could be the motor going backways (probably unlikely) but I would first take out the blue gear and check for wear. Also check the small needle bearing 'clutch' (hf1216 ?). Blue gear should turn freely on shaft one way only. This can fail (sometimes from over-greasing the blue gear).
Plenty of instruction videos on You tube. e.g.