TSDZ2 vs BBS02

This post contains affiliate links, to find out more information, please read my affiliate disclosure


In this TSDZ2 vs BBS02 comparison I will offer my opinion on these mid drive electric bike conversion kits. Over the last couple of years I have installed more than a hundred Bafang mid drives, and more recently around twenty Tongsheng systems.

At the bottom of this article I have placed useful links on where to purchase the BBS02 and TSDZ2


Both the Tongsheng TSDZ2 and the Bafang BBS02 are market leaders in mid-drive electric bike conversion kits, with the latter having a substantially larger slice of the pie.

Bafang BBS02

The Bafang motor is well-established, and despite some ongoing reliability issues, still offers the most bang for your buck. A BBS02 750w will kick out close to 1500w with a 52v battery fitted. This will transform your humble bicycle into a high performance speed machine (but the 52v battery will compromise reliability). I always recommend sticking with a 48v battery, unless you are willing to shell out for replacement controllers.

Bafang BBS02 750w mid drive electric bike conversion kit

The pedal assist system (PAS) on the Bafang motor acts like an on/off switch. As soon as the pedals rotate a few degrees, the motor kicks in. The pedal assist on all the Bafang BBS motors can be fine-tuned with controller programming and careful selection of the 9 available power levels.

With this method of pedal assist you just have to turn the pedals to get assistance, you don’t have to put a lot of effort in. It is possible to climb a 25% gradient in a low gear with the power level set to 9. All you will be doing is spinning the pedals, the motor will be doing most of the work!

The BBS02 has a lot of potential for fine-tuning. Being able to reprogram this motor is a real bonus.

It should be noted, that compared to a normal bike the Bafang is harder to pedal when the motor is switched off.  This is not so much of an issue when cycling on the flat, but if you find yourself out of battery power, pedalling up a steep hill can be practically impossible.


The BBS02 has a lot of potential for fine-tuning. Being able to reprogram this motor is a real bonus, and in some cases necessary. In my experience, the factory pedal assist settings are not very good, in particular the way the pedal assist stops and starts. Thankfully these can be changed in a matter of minutes by connecting your motor to your laptop using a Bafang USB lead and this free open source software.

Tongsheng TSDZ2


The TSDZ2 has been around for a while now, and early reliability issues seem to have been resolved. It is now a very viable alternative to the Bafang BBS02. And unlike the Bafang, Tonsheng specifically lists a 52v version.

tongsheng tsdz2 with colour display


The main difference between these two motors is the pedal assist. With the Tongsheng it is not a free ride. You are rewarded with more power only if you put the effort in.

The progressive surge of power you get in sport mode really does make you feel like the bionic man!

The Tongsheng uses torque sensing pedal assist. This gives you motor-assistance proportionate to how much force you are applying to the pedals. This makes for a very intuitive system right out-of-the-box.

Even using the 48v750w version, you still have to put some degree of effort into pedalling in order for the motor to work. I really like this, as it feels a like a Bosch motor on steroids!

The progressive surge of power you get in sport mode really does make you feel like the bionic man! The motor feels more like an extension to your own cycling abilities.


If you prefer to ride at a high pedalling cadence, it is worth noting that these motors do not produce any noticeable assistance above 90rpm. The initial burst of power fades quickly when these high cadences are reached, even though force is still being applied to the pedals.

With the motor switched off, the Tongsheng wins, hands down over the Bafang. Although there is some increased pedalling resistance, it is nowhere near as noticeable as on the BBS02.

If the BBS02 is the lazy man’s electric bike conversion kit, then the TSDZ2 is for people that don’t mind working up a bit of a sweat. Although the 500w and 750w versions are substantially quicker than their lower powered counterparts, you still have to put in some effort to get the motor working.

The only downside with the Tongsheng motor, is programming the controller. It is possible but it is not as straightforward as with the Bafang, also you are limited to only 4 different levels of assist versus the Bafang’s 9 levels.

Pro’s and Con’s

Bafang BBS02


  • Very responsive pedal assist
  • 9 levels of pedal assist
  • Good spare parts availability – click here for list of parts
  • Programmable
  • Well established brand
  • Very powerful


  • Some reliability issues still persist
  • Pedalling resistance, when motor is switched off
  • The motor may need periodic tightening
  • More expensive than the Tongsheng
  • Feels more like an electric motorcycle (not a bad thing, if that is what you are looking for)
  • Stock controller settings are not very intuitive



  • Intuitive torque sensing system
  • Easier to pedal than the Bafang when the motor is switched off
  • Lighter than the Bafang
  • Can provide a ‘more natural’ cycling experience
  • Very efficient motor / increased battery range
  • Parts availability is good – click here for a parts list
  • Great value


  • A certain degree of pedalling effort is required to start the motor – this may not be suitable for everyone
  • Programming is possible, but not as straightforward as the Bafang
  • Only 4 levels of assistance
  • The motor does not give any noticeable assistance at high pedalling cadences.
  • The blue nylon primary gear can be prone to premature failure
  • Although the torque sensor is generally reliable, it has been known to fail.



Both of these motors are excellent in their own way, but the choice really boils down to your own personal preferences.

If you want an enhanced cycling experience, with the motor feeling like an extension to your own ability, then the Tongsheng is definitely the way to go. If you have a medical condition that limits your ability to pedal hard, then the Bafang may be more suitable.

Either way, both of these motors are great fun. If I had to make a choice, based on my own personal experiences, then I would have to choose the Tongsheng over the Bafang. Unfortunately I have had a disproportionately high amount of controller failures with the BBS02, and my confidence in their long term reliability has been tarnished. To date I have had no major issues with any TSDZ2 I have installed.



If you are concerned about the current e-bike laws, it is worth remembering that both the BBS02 and 500w / 750w TSDZ2 are not road legal in the UK, EU or Australia. If you do choose to use them on the road you do so at your own risk and most importantly you need to consider the potential risk to others. Please read my guide to electric bike law here.

If you choose to go down this path, make sure at the very least you limit the top assisted speed to 25km/h (15mph) and ride sensibly. The consequences could be dire if you were to have an accident riding one of these on the road – RIDE SAFE!

Below are some links to vendors of the Bafang BBS02 and Tongsheng TSDZ2

Buy the Bafang BBS02 750w

bafang bbs02 mid drive electric bike conversion kit
Buy on eBay
Buy on Aliexpress
Buy on Amazon

Buy the Tongsheng TSDZ2 36v / 48v / 52v

Tongsheng TDZ2 250w - 350w - 500w - 7502 36v 48v 52v
Buy on Aliexpress
Buy on Amazon
Buy on eBay



Please follow and like us:

16 thoughts on “TSDZ2 vs BBS02

  • March 3, 2019 at 5:46 pm

    Good comparision.
    I´ve been a BBS02 fan for years because of it´s good power, programmability and robustness.
    Now i´ve tried two Tongshengs, one for my wifes trailbike, one for commuter bike and have to say that for serious MTB action this is the better motor. It works fine out-of-the-box, needs no special programming (which is much more complicated than on the BBS). The noise is far away from what my Bosch Performance is producing, this was different for the “older” from 2014 – 2016. Yes, ground-clearance as well as chainline is worse than Bafang, but still acceptable. In Germany, the Tongsheng can be found for 320 € on eBay, which is 20 % less than a BBS02.

    When robustness is only limited by the blue nylon gear, this is no problem. Time will tell.

    • March 3, 2019 at 7:44 pm

      I agree, the BBS02 is a great motor. I covered just under 2k miles in under 12 months and never had any issues.

      I’m planning on building a utility e-bike this Spring/Summer for small shopping trips. My doner bike is going to be a Kona UTE or Surly Big Dummy and will be using the TSDZ2 as I prefer the torque sensing pedal assist.

      It is definitely a more refined motor than it used to be, and the general reliability has improved.

      • July 25, 2019 at 6:44 am

        I need a mid-engine for my wife’s bike. She’s not very sporty, so I need an engine with 100% support, especially since the way to our house has 13% incline. My wife has a city bike that I want to rebuild. Bafang or TSDZ2 ?
        Regarding the TSDZ2 I’ve read that the 36V 250W version should be more powerful than the 36V 500W version. Is that correct ? And what’s about the 36V 350W version?

        Thank you, V.E.

        • July 25, 2019 at 7:24 am

          I have installed and ridden all of the above versions of the TSDZ2 and the 500w has noticeably more power than the 250w version. The difference between the 36v 250w and 350w model is minimal. The Bafang BBS02B 36v 500w (36v x 25A) is considerably powerful than the TSDZ2 36v 500w (36v x 16A).

          I personally prefer the torque sensing pedal assist of the TSDZ2 (my ebike has the 36v 500w version fitted), but for maximum pedal assist the Bafang is hard to beat.

          If you require any more information on these motors, please let me know.

          All the best,

  • July 6, 2019 at 7:02 pm

    I have bbs2 on my Mtb and also tongsheng on my. Rickshaw tricycle ,taxi bike where i transport. 2 more peoples around the city. The blue gear broken after one month. I take the metal gear also 1 month was Broken .
    So if the bafangs gear stronger i dont try to my Rickshaw i definitely say bafang. But. I need to try. Because ones the month geañr fñor 25€ costs lot and Steeling my time

    • July 7, 2019 at 9:15 am

      Unfortunately the blue gear is a weak point on the Tongsheng, especially if you are carrying a lot of weight. You would definitely be better off with a Bafang BBS02 or BBSHD on your Rickshaw.

      • September 19, 2019 at 5:36 pm

        Blue gear is a weak point on Tongsheng but can be easily replaced with a metal gear. This adds a bit of noise but addresses reliability concerns. I do like the natural way the power comes on with the Tongsheng which made this worth it for me.

        • September 20, 2019 at 8:31 am

          Hi Dave,

          Thank you for your comment. I totally agree, the TSDZ2 is a great motor and the extra noise you get with the metal gear is minimal in my opinion.


  • September 30, 2019 at 10:35 am

    I started looking into mid drive conversions for my old cannondale Jekyll earlier this summer and came across Tonys E bike choices blog , I must say this guy knows his stuff and cant do enough to assist you.After a long chat i was sure the Tongshen was for me as i wanted the torque assist and not just create an electric moped ! I am located in South Suffolk so located quite a way from Cornwall but being a hands on type of person was more than happy to tackle the conversion. My cannondale being a full suspension bike did need a minor modification to the swing arm but apart from that installation was straighforward enough. I have now covered 200 miles and apart from occasional chain off situation when down shifting too fast i can say it has transformed my bike into a stealth hybrid and i can now commute to work with assist and not need a change of clothes and ride home for a workout !
    Many thanks Tony for all your help

    • September 30, 2019 at 10:02 pm

      Hi Andrew,

      Thanks for your positive comments. If you ever need any more assistance, give me a shout.


  • November 2, 2019 at 1:42 am

    I’m hoping to convert a Trek hybrid to an ebike. I have long term sciatic pain and I’m about to start touring in a campervan.
    I think I would like the Tongsheng TSDZ2 48v 750w version.
    Is this legal in the EU and UK? I have a full motorbike license.
    Also what battery would be optimal for this motor?

    • November 2, 2019 at 3:26 pm

      Hi Eric,

      The 750w version would not be legal for road use in the UK or EU, unless there was a way you could get your bike approved and registered by the DVLA.

      It would be subject to the same rules as a moped – insurance, lights, indicators etc.

      I’ve converted quite a few bikes using 250w version for customers with knee problems and they have found that to be more than adequate.

      If you did decide to go for the 750w, I have fitted quite a few of these 48v 13ah batteries without any issues.

      If you need any more advice, please let me know.


  • January 19, 2020 at 2:00 am

    Hi Tony, I had a Tsdz2 installed on my Intense Uzzi a month ago. Initially, I was very pleased with the results. But after 160km, I noticed a great deal of creaking and groaning from the bottom bracket. Removed the emotor and found that the guy I got the TS from in Malaysia, had hacked off a large chunk of the Uzzi’s down tube so that the emotor could nestle there. He had just slapped the whole thing together again using just epoxy. Moral of the story is, when you send a frame to have an emotor fitted, you must send it to someone who knows what he is doing. I even told the clown he couldn’t drill a hole in the tube when he wanted to. So now I have a ruined frame. Wish I could post a pic of the damage!

    • January 19, 2020 at 5:53 pm

      Hi Mak,

      Sorry to hear that. I would take your bike back to the person that bodged the conversion and ask for compensation. Those Uzzi frames are expensive.

      Let me know how things go.

      All the best,

  • February 9, 2020 at 2:03 am

    Hi from Australia, I’ve used 2 Tongsheng drives on road bike with Gates and NuVinci hub drive, both motors worked GREAT but unfortunately they develop noise issues , l had to replace Spragg clutch at 1100kms blue gears okay, replaced internal bearings and spragg bearing with Japanese and German equivalents. The internal friction noises rubbing and creaking are from torque sensor unit which has two faces rubbing 100% of the TIME. These noises developed at 1500kms approx, second motor is making similar noises at 700kms, I’m about to replace 36v Tongsheng with BBS02B , hoping to have no noises.
    Can anyone tell me if BBS02B is progamable using available software and USB CABLE?
    Hope this information is useful, Tongsheng motors are GREAT to use but torque sensor unit is a let down.

    • February 9, 2020 at 10:34 am

      Hi Kevin,
      Thank you for sharing your experiences with us. The Tongsheng has the potential to be a great motor, if they improved the durability of the components. Regarding the Bafang BBS02B, I covered over 3000kms without any issues. The BBS02 is easy to program using the USB lead and you can really make the power delivery smooth and progressive. I used ‘Karls special sauce’ programming parameters. Here is a link to the details, there is also a link to the free software download.

      All the best,


Leave a Reply

Your email address will not be published. Required fields are marked *