Surly Preamble mid-drive conversion
 

Hi all! I’m wanting to convert my surly preamble using a mid drive motor and had some questions. Been doing some research and it seems like a motor with torque sensing is what I’m looking for so I’m looking at 3 motors: Cyc, tsdz2, & the Toseven. Would love to not spend $1000 on just the motor so leaning away from Cyc but have heard mixed reviews about tsdz2 and Toseven seems promising but is fairly new so maybe still working out kinks?

Does anyone with torque sensing motors have any advice?

Also what size battery would I want for a daily commute of about 15 miles total— just looking for some uphill assist so nothing crazy.

Try to ride a mid-drive with torque sensor.I'm very happy with my BBS02 after 10+ years of off road (mostly) riding. This system, one of three in my family has never required maintenance nor failed (same for the others). IMO, the CYC is too expensive and the TS has too many problems (although I'm sure someone will chime in that theirs works fine).

yeah I’d like to test drive one but just based on research and some videos, it seems like torque sensing makes the ride feel like you are still riding a bike versus with what I understand about cadence sensing once you start peddling the power takes over?

I use my enhancement mostly when ascending and can adjust the PAS to get the desired exercise. The advantage for someone in your situation is you could regulate the system to use as much leg power as desired and keep up. That might not be possible with a torque-based bike.

yeah I’d like to just have it for inclines as they just take too much energy these days. With a motor like the Baafang, can you set it to only engage when you’re on hills or will the motor be running any time you pedal? I’ve honestly just seen reviews of cadence sensor motors that say it feels like you’re riding a moped more than a bike bc your pedaling isn’t actually doing much, the motor is

The BBS's PAS can be set to "0" and you'll be on leg power alone (but with a heavier bike), then adjusted to the desired level when necessary. This could be a PITA if you need to change back and forth frequently. I didn't install a throttle, but it's possible to set the system as throttle only and use it as necessary.

Yeah, I'd describing it as feeling like you are spinning the pedals to activate the motor, vs feeling more like a normal bike. The first few days I had the BBS02 I hated the feeling, then quickly adapted to it. I'd say it still has enough of the feeling like riding a bike that I don't regret getting it. If I were starting from scratch, I'd be tempted to go for the CYC Photon.

My battery is 16Ah, under ideal conditions I tend to get 40 miles per charge with how I ride, when winter riding it can drop to 15 miles per charge.

thanks for the input! I found this company Toseven that makes torque motors and they’re about half the cost of CYC bc they’re pretty new but getting good reviews, Johnny nerd out sells them on his shop so thinking of going that route.

At this point just trying to figure out what battery I should get (have about a 15 mile daily commute and only plan to use assist on hills)

I've converted bikes to the three lower cost mid drives, bafang BBS02B, Toseven DM02, and Tongsheng TSDZ2,

If you want the proverbial two wheel locomotive, the BBS02 pulls like a train. I've put 1600 miles on one I converted in 2016. The TSDZ2 out of the box is weak and requires strong pedal effort, but the third part firmware (free) makes it respectable, My wife and I have 4200 miles in the last two years on a pair of TSDZ2 conversions with OSF firmware. The DM02 has plenty of power out of the box, and the torque sensor works well, I have 400 miles on my DM02 conversion.

Based on actual measured currents from riding them, I believe a newer BBS02B will draw about 18-20A max from a 48V battery, while the other two are 14A max. For commuting, you want the bike that goes the fastest with the least effort, so you can concentrate on safe riding rather than pedalling. The BBS02B would be best for that, The DM02 is good for solo riding at 16-18 mph. The TSDZ2's are for bike path riding with your friends.

thanks for the insight! The BBS02B is a cadence sensor right?

so it sounds like you’re happy with your DM02? I could also do the DM01 for extra power but didn’t think I’d need? I’m looking at 52v 14ah slim shark battery

Yes. Am happy with the DM02. I don't worry about speed because there's always the BBS02B for that, The DM02 powers a steel 10 speed from 1975, and the BBS02B is a Diamondback from 2005.

I took the blue bike out today in the cold weather. It would be my choice if I had to be somewhere on time,
https://cimg7.ibsrv.net/gimg/bikefor...08a8f4333.jpeg