So I've been spending a lot of time researching e-bikes lately, specifically wanting to create a good full suspension e-bike. I rode a Haibike and that was amazing but I wasn't ready to spend over NZ$6000! Especially when I already have a nice bike. Having spent time researching and riding I realised that a torque sensor is really important for off-road use. And like the others here I came across the TSDZ2 and took the plunge.
So, what do I think? The motor and display all seem very nicely made. The motor delivers plenty of power and shoves me up my very steep driveway with no problem at all - even driving a very high gear due to the large chainring. The torque sensor definitely works and you can feel the dollops of power being delivered as you push down with each peddle stroke. And here's where I come to the problems:
1) It does literally deliver power with each peddle stroke. As the peddles move along the horizontal plane you aren't activating the torque sensor and power drops off dramatically. There seems to have been no attempt to smooth this out in the controller at all.
2) With road use I find it almost pointless as it delivers virtually no assist unless you're pushing a gear so high that you need to be peddling really hard. Even at maximum setting you don't feel any assist unless you're accelerating.
3) Mine didn't come with the programming cable and I'm struggling to buy one
4) I fitted a 34 tooth chainring by grinding off a little off the end of each mount point - to stop it interfering with the chain. This certainly helped gearing but because it isn't an offset chainring there is a lot of chain bend when driving the largest rear sprocket.
So while this unit shows a huge amount of potential and has the ability to deliver plenty of torque sensored assist, the implementation is not good. Maybe I can improve it if I manage to get hold of a programming cable. I really hope so.
I'd love to hear other peoples experience. Maybe together we can work out how to improve this unit. Or maybe we can collectively respond to Tongsheng Bicycle Co and get them to make some changes. Who knows