Tongsheng TSDZ2 Torque sensing Mid Mount conversion

Sgarth42

Member
Oct 13, 2021
73
51
York
I have been riding a converted Giant Trance 4 with a Tongsheng TSDZ2 Torque sensing motor for nearly a year now. I am amazed how quiet the motor is (even compared to my mates Bosch) and many in my riding group have also commented the same. I upgraded the factory software with opensource software which has improved the start-up assistance from the torque sensor and continues to give PAS to 120 cadence. I am genuinely surprised these are not getting mentioned more. Very simple and easy to repair (if needed) and not hugely expensive. Breathes new life into your old MTB. Is any one else using one?

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ebsocalmtb

Active member
Sep 29, 2021
232
245
Southern-Cal
First post for me. I actually built one of these up on a Santa Cruz Chameleon frame. I am actually in the process of either parting out this frame or selling the bike complete as I have an orbea rise coming in soon. I too was blown away on how good this setup is considering the cost of entry. This is for sure the only diy mid drive that actually feels like an OEM built ebike. There are still drawbacks and this motor needs a whole host of modifications in order to perform at it's best; thermal capacity mods, firmware, bottom bracket spindle/width adjustment, offset drive side crank, chainline issues if you have a bottom bracket or chainstay width that requires greater then 73mm spindle etc etc. However it's very easy to build one of these up and have less then 800 bucks in the electronic drivetrain components.

I actually built this bike as a commuter setup and didn't really have much in the way of expectations for it's abilities on dirt. I have definitely been pleasantly surprised about how capable it is and as long as you aren't doing drops/jumps on it, I feel like it would be pretty reliable.

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It performed well enough to schlep my 71 year old father around on some fire roads.
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Sgarth42

Member
Oct 13, 2021
73
51
York
First post for me. I actually built one of these up on a Santa Cruz Chameleon frame. I am actually in the process of either parting out this frame or selling the bike complete as I have an orbea rise coming in soon. I too was blown away on how good this setup is considering the cost of entry. This is for sure the only diy mid drive that actually feels like an OEM built ebike. There are still drawbacks and this motor needs a whole host of modifications in order to perform at it's best; thermal capacity mods, firmware, bottom bracket spindle/width adjustment, offset drive side crank, chainline issues if you have a bottom bracket or chainstay width that requires greater then 73mm spindle etc etc. However it's very easy to build one of these up and have less then 800 bucks in the electronic drivetrain components.

I actually built this bike as a commuter setup and didn't really have much in the way of expectations for it's abilities on dirt. I have definitely been pleasantly surprised about how capable it is and as long as you aren't doing drops/jumps on it, I feel like it would be pretty reliable.

vyR6R2q.jpg


IZRetrY.jpg


qC6auWJ.jpg


U8LyPoa.jpg


wW5NMA7.jpg

jE2ROkc.jpg


It performed well enough to schlep my 71 year old father around on some fire roads.
6dS7pUH.jpg
I agree with all your points - but for what is and what it costs, I am still blown away with it capability. It can be used out of the box and yeah I needed to do quite a bit of modification and adjust to fit the Giant but there are many bikes with STD bottom brackets that it will just slot straight in. By the way I am very impressed with the front retaining bracket, may I copy that?
 

ebsocalmtb

Active member
Sep 29, 2021
232
245
Southern-Cal
I agree with all your points - but for what is and what it costs, I am still blown away with it capability. It can be used out of the box and yeah I needed to do quite a bit of modification and adjust to fit the Giant but there are many bikes with STD bottom brackets that it will just slot straight in. By the way I am very impressed with the front retaining bracket, may I copy that?

Absolutely. That bracket is actually a bafang BSBF-1 stabilizer mount (sourced through lunacycles BSBF-1 Stabilizer Bar for BBS02 and BBSHD). You end up having to do some re-bending of the mount and re-drilling the tabs to make it work with the TSDZ2 but it's not all that difficult. I've included a few more photos of it here so that you can see how I went about it. FWIW, I just templated it in card stock first, then cardboard before I went re-bending the mount in order to fit it to the bike. I specifically used this chameleon frame with this mount in mind because It had pre-brazed/mounted bottle cage bosses in the perfect location. In your case, I'd suggest worm clamps and rubber to mount the torque arm to the frame.

I can't believe i'm saying this, but I'm actually having a bit of a problem convincing myself to sell this bike, and or part out the kit. This thing will hammer along at 25mph with mtb tires on flat ground averaging 350w nominal without issue. It is definitely a pretty dang good setup provided you have the right expectations going in, I think most people would come out the other end quite content.

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Sgarth42

Member
Oct 13, 2021
73
51
York
Absolutely. That bracket is actually a bafang BSBF-1 stabilizer mount (sourced through lunacycles BSBF-1 Stabilizer Bar for BBS02 and BBSHD). You end up having to do some re-bending of the mount and re-drilling the tabs to make it work with the TSDZ2 but it's not all that difficult. I've included a few more photos of it here so that you can see how I went about it. FWIW, I just templated it in card stock first, then cardboard before I went re-bending the mount in order to fit it to the bike. I specifically used this chameleon frame with this mount in mind because It had pre-brazed/mounted bottle cage bosses in the perfect location. In your case, I'd suggest worm clamps and rubber to mount the torque arm to the frame.

I can't believe i'm saying this, but I'm actually having a bit of a problem convincing myself to sell this bike, and or part out the kit. This thing will hammer along at 25mph with mtb tires on flat ground averaging 350w nominal without issue. It is definitely a pretty dang good setup provided you have the right expectations going in, I think most people would come out the other end quite content.

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wPWiice.jpg


zuRGbVn.jpg
Thanks - info much appreciated. As you can probably tell by the conversion, I enjoy a bit of fabrication & fettling. Have you tried flashing the motor with the OSF? It's much better. Incidentally, I use mine at bike parks and trails. I'm too old to attempt big jumps but despite the motor being low slung, I have so far not had any occasions where it has grounded of being hit and feel pretty comfortable with it.
 

ebsocalmtb

Active member
Sep 29, 2021
232
245
Southern-Cal
Thanks - info much appreciated. As you can probably tell by the conversion, I enjoy a bit of fabrication & fettling. Have you tried flashing the motor with the OSF? It's much better. Incidentally, I use mine at bike parks and trails. I'm too old to attempt big jumps but despite the motor being low slung, I have so far not had any occasions where it has grounded of being hit and feel pretty comfortable with it.

yeah my setup is fully modified using the OSF. I've done the temp sensor mod, 100mm spindle, brass gear, thermal mods (more on that below), 42t 10mm offset narrow wide chainring and I added 2 bearings to the spindle to help distribute the load better.

The most impactful modifications you can make to this motor really is the OSF and the temp capacity modifications. I've thrown the kitchen sink at this one with regards to temp mods, including: silent thunder ordinance heat sink shim plate, thermal paste between motor stator and flanges, thermal paste between motor and casing and thermal putty and aluminum shims between the non-drive side of the motor and the non-drive side housing. Prior to the thermal capacity mods, this thing could barely output 200w for 20 minutes without overheating. Now that I have done all of those mods, it seems nearly impossible to over heat it, and it can crank power out without much issue.
 

Sgarth42

Member
Oct 13, 2021
73
51
York
yeah my setup is fully modified using the OSF. I've done the temp sensor mod, 100mm spindle, brass gear, thermal mods (more on that below), 42t 10mm offset narrow wide chainring and I added 2 bearings to the spindle to help distribute the load better.

The most impactful modifications you can make to this motor really is the OSF and the temp capacity modifications. I've thrown the kitchen sink at this one with regards to temp mods, including: silent thunder ordinance heat sink shim plate, thermal paste between motor stator and flanges, thermal paste between motor and casing and thermal putty and aluminum shims between the non-drive side of the motor and the non-drive side housing. Prior to the thermal capacity mods, this thing could barely output 200w for 20 minutes without overheating. Now that I have done all of those mods, it seems nearly impossible to over heat it, and it can crank power out without much issue.
Links to the thermal putty that you use if you don't mind. That's my next job. Tend not to use with anywhere near full assist but am sure it must be getting hot at times ( even in cold uk) Really tidy build by the way. Well done
 

ebsocalmtb

Active member
Sep 29, 2021
232
245
Southern-Cal
Links to the thermal putty that you use if you don't mind. That's my next job. Tend not to use with anywhere near full assist but am sure it must be getting hot at times ( even in cold uk) Really tidy build by the way. Well done

I sourced the motor and the putty through eco-ebike.com here in the US. They sell some very expensive 10w/mk putty that is enough to pack into the motor housing. It's unfortunately, priced quite well as finding this stuff in reasonable quantities elsewhere, netted far more expense from my research. you can also source the silent thunder oridinence shim plate from them as well. At this following link. TONGSHENG TSDZ2 - OSF MODEL SPECIFIC PARTS

there are more cost effective, DIY solutions that do not involve the putty, and some of this can be done with good ole off the shelf pc/cpu thermal heat paste. There are a plethora of ideas for dealing with heat dissipation at the following link. Hardware temperature control tsdz2 - Endless Sphere
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
Been using these motors for 6 years or more, contrary to popular belief you don't need to do all the heat sink mods. We have had 6 of us running pretty standard units over some pretty hilly conditions, we've not seen any motors that have over heated in the excess of 10K miles we have done, despite modding them to in excess of 750W's. The OSF firmware has developed over the years to be probably as good as the best.

For anyone interested in upgrading your exisiting bike to a full on 750W torque sensing EBike for £ 279.00 delivered to your door for the motor kit, then you can't go wrong. Do they go wrong, yes typically from water ingress, but no worse than the major brands. Parts are widely and cheaply available, but at that price, we've almost got to the throw away, fit a new one stage.

Endless Sphere is full of info on the motors, start at the beginning for good night time reading.

 

Mabman

E*POWAH Elite World Champion
Feb 28, 2018
1,126
1,856
Oregon USA
My first TSDZ2 Christmas of '17

Screen Shot 2021-10-13 at 6.00.56 PM.png

I did manage to munch the plastic gear right away and went to the brass gear. Also put a 52v controller/battery on right away. Lunched the bb bearing, at around 1500. Never had any overheating problems, even getting way up there.

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Instead of fixing that motor I just got an OSF equipped 48v model as I started using the 52v battery on my gravel bike. I had also just gotten a 48v 21700 cell battery I wanted to use. No notable performance improvement overall that I could tell.

I switched all the parts over on to my FS frame a few months ago

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and continue to enjoy riding the TSDZ2 but as soon as a decent M600 deal comes my way I'm going to invest in one. But I'll keep my TSDZ2 thing going also as a buddy bike.

I agree that with the plastic/nylon whatever gear it is about as quiet as anything I have ridden with and at least as powerful. The biggest drawback is that you are stuck with a 42t chainring, I use an offset one custom mounted onto a stock spider for great chainline, and so you can't do steep switchbacks as well as if you had a 36t like my buddy has on his Levo.

I also have a Roadster version I put together for some dirt road fun with a 48v OSF setup.

Groadster dt side.jpg


So overall not a bad way to get into eBiking at about a grand for a motor and battery or a bit more and some tinkering. If you have a good bike that it will fit that is.

I never bothered with any hold down strap as shown and just let it ride up against the dt and haven't had any issues in over 4k of use btw.
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
I did manage to munch the plastic gear right away and went to the brass gear. Also put a 52v controller/battery on right away. Lunched the bb bearing, at around 1500. Never had any overheating problems, even getting way up there.
The plastic gear was one of the least reliable parts of the motor in its early iterations, it was almost always user error of starting in too higher gear and stomping on the pedals as you were in too higher gear, to get going ( the motor is so torquey that it will pull from 0 revs ). The motor seeing the high load on the pedals would ramp up and with the rear wheels effectively at standstill, something has to give ( better that than damage a main steel gear or belt ). I too have done a couple but more in trials like situations where you are trying to lift a front wheel over an obstacle at a virtual standstill. They take 30 minutes to change, cost £ 20.00, we keep them in as they are good safety fuse and much much quieter than the Brass replacements.

The OSF firmware was specifically initially designed just to prevent this and now speed of the rear wheel and torque sensing are linked with the user able to set up to their hearts desire virtually all phases of the ramp up and virtually all other parts of the engine cycle. Recent versions now have FOC to maximise the cadence and efficiency, the OSF firmware has now got to the stage where its good, very good and compared to my M600 motor, its much better in a lot of ways.

The interesting thing is that on a good bike such as my Whyte T129, with motor and battery fitted, I think its around 18 kgs, one of the guys converted a very trick 26" enduro bike and it was around 15kgs.

There is an after market adaptor that takes a standard 104BCD narrow wide chain ring, I presently run a 36T.

But, and I'm not sure why, we as a group have all trended towards state of the art EBikes, with a trend of the Trek Rail and Levo beginning to appear. My E10 Cheeb is good but so heavy compared to my Whyte :rolleyes: Great geat way as an entry into Ebikes, keep the power levels down to below 600W's and they seem to last forever.
 

Sgarth42

Member
Oct 13, 2021
73
51
York
I sourced the motor and the putty through eco-ebike.com here in the US. They sell some very expensive 10w/mk putty that is enough to pack into the motor housing. It's unfortunately, priced quite well as finding this stuff in reasonable quantities elsewhere, netted far more expense from my research. you can also source the silent thunder oridinence shim plate from them as well. At this following link. TONGSHENG TSDZ2 - OSF MODEL SPECIFIC PARTS

there are more cost effective, DIY solutions that do not involve the putty, and some of this can be done with good ole off the shelf pc/cpu thermal heat paste. There are a plethora of ideas for dealing with heat dissipation at the following link. Hardware temperature control tsdz2 - Endless Sphere
Thanks, I have spoken with David before at Eco_cycles and bought parts. He has been a brilliant help in that past, I had a look for that kit and didn't see it. Thanks for the link - will contact him.
 
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Sgarth42

Member
Oct 13, 2021
73
51
York
My first TSDZ2 Christmas of '17

View attachment 73736
I did manage to munch the plastic gear right away and went to the brass gear. Also put a 52v controller/battery on right away. Lunched the bb bearing, at around 1500. Never had any overheating problems, even getting way up there.

View attachment 73742



Instead of fixing that motor I just got an OSF equipped 48v model as I started using the 52v battery on my gravel bike. I had also just gotten a 48v 21700 cell battery I wanted to use. No notable performance improvement overall that I could tell.

I switched all the parts over on to my FS frame a few months ago

View attachment 73741

and continue to enjoy riding the TSDZ2 but as soon as a decent M600 deal comes my way I'm going to invest in one. But I'll keep my TSDZ2 thing going also as a buddy bike.

I agree that with the plastic/nylon whatever gear it is about as quiet as anything I have ridden with and at least as powerful. The biggest drawback is that you are stuck with a 42t chainring, I use an offset one custom mounted onto a stock spider for great chainline, and so you can't do steep switchbacks as well as if you had a 36t like my buddy has on his Levo.

I also have a Roadster version I put together for some dirt road fun with a 48v OSF setup.

View attachment 73740

So overall not a bad way to get into eBiking at about a grand for a motor and battery or a bit more and some tinkering. If you have a good bike that it will fit that is.

I never bothered with any hold down strap as shown and just let it ride up against the dt and haven't had any issues in over 4k of use btw.
You mention stuck with 42T chainring, I fitted an aftermarket spider on my wife's converted bike (I know the battery is not best placed) with 38T narrow/wide. Chain-line is spot on

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Mabman

E*POWAH Elite World Champion
Feb 28, 2018
1,126
1,856
Oregon USA
I'm glad that others have found solutions they are happy with for their TSDZ2 use. However, especially in regards to chainline there is no way that I can see to get a proper chainline, due to the gear reduction housing, without having a ring that will straddle it moving the chain inwards and the housing size is such that only a 42t will fit. Anything that sits outside the housing will not work for me at least.

And my first blue gear failure was due to a very tiny piece of the vane that chipped off and resulted in a slight crunching noise that led me to the brass gear extra noise be damned. I did really crunch another newer compound gear on my replacement non OSF motor when I was starting off on a tight trail from a standstill when I had used a blip of throttle to get a little momentum going my front wheel hit an imovable object that was hidden from view and stopped me dead just as I put force on the pedal and the end result was as suggested. However I wasn't in too tall of a gear it was just an unfortunate thing that happened but I have been careful to not repeat it. I was able to limp home however and install the brass gear I had from my other motor but did replace it with another blue gear which has been fine since.

The DIY game is not for everyone and there is alot of latitude in just how to go about it even using basically the same componentry. I find that whatever works and taking tips from other users that might make it better does help but I personally don't subscribe to all the things being done.
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
For what the cost, they are brilliant.
Very capable within their comfort zone
And that’s the main point, they are not the Mercedes of the bike motor world, more like the Skoda, but if you already have a pretty good donor bike, then you can buy 15 engines and 2 batteries for the same price as a mid range EBike and the modern day Skoda being VW based, is pretty darn reliable.

Will a conversion using the TSDZ2 be as good as that mid range EBike with all its modern geometries 29er wheels and 150mm up to date suspension, absolutely not. What do you expect, let’s get real. But what you will have is a great entry level bike that you can dip your toes into the EBike world at relatively little cost.

Will you move onto a purpose built EBike, almost certainly, as my group has done. When that old faithful really has worn itself out, we’ve replaced them with a new proper all singing and dancing model.
 

Mabman

E*POWAH Elite World Champion
Feb 28, 2018
1,126
1,856
Oregon USA
"Will you move onto a purpose built EBike, almost certainly, as my group has done. When that old faithful really has worn itself out, we’ve replaced them with a new proper all singing and dancing model."

Pretty much where I am at, especially after riding my mates new Trance a few months ago. I have been riding mtb's since day 1 pretty much and for sure I could tell the difference in geo and sus travel and liked it.

However I have also been hip to e power since 2001 when I got my first Currie kit and also a front hub drive soon after to see what the possibilities might be of assist. Found the battery tech to be wanting and figured it would catch up some day and it finally did. I bided my time with several 4 stroke 49cc endeavors in the meantime and so all my rides were throttle equipped and had good pedaling drivetrains also. So I got used to having a throttle on board and when the battery finally got to the point I knew it would give me a better taste I also stuck with a throttle and pedal setup.

That resulted in a couple of front hub gravel type bikes that I could set on cruise control when on the road and pedal away unabated by any motor influence. It wasn't until I wandered into a shop that had some TongShens in stock and figured out they had torque sensing and a throttle that I put down for one to convert my mtb.

So I know that it is not cool to have throttles, and in fact here in the US those that do are considered Class 2 citizens, but for the <1 mile of use I get out of having one on board for every 1000 miles traveled and the fact that they weigh next to nothing I wouldn't own an eBike without one,

Thus my interest in the M600 which is the only integrated 750ish watt/decent weight motor available primarily thanks to the Draconian EU regulations against any throttles allowed that has the Class 1 folks here all righteous also although our Federal regulations make no distinctions about them.
 

ebsocalmtb

Active member
Sep 29, 2021
232
245
Southern-Cal
Pretty nice builds here. I sorta disagree that these can be run without the temp capacity mods. I wouldn't bother with the temp sensor addition/mod on future builds, but I would opt to do the STO shim plate, cpu thermal grease between the flanges of the motor/stator, and pack the non-drive/dry controller side of the motor housing with either putty or thermal pads. It might just be my location and the fact that I'm huffing this thing up legitimate mountains and whatnot in 90 degree ambient (32c) temps often... but this thing will overheat pretty quick when putting out over 400watts on flat ground. Less so during actual trail riding as the load is so varied. One last notable thing with that... these stay cooler with a lower cadence. I have a pretty fast cadence as as pretty fit mtb rider to start off with (90+) and the FOC and resulting motor RPM, over 4,000, does cause these to build up heat faster then a 60-70 cadence and a motor rpm of 3,500-4,000. That seems like what is optimal for this motor.

Regarding chainline... that is the biggest drawback for these DIY mid drives, especially on modern boost frames. Any frame boost frame, particularly 29r made after about 2014 +/- that provide 2.4+ rear tire clearance, become difficult. I remedied this by making a 8speed drivetrain, based on 11 speed components and spacing. My trick to this was to use a 11-46 shimano SLX cassette, and to pull some of the cogs out. That cassette has the 3 largest climbing gears on an alloy spider, and then I pulled a few of the mid cogs out of the mix. this essentially allows me to improve the chainline in the granny gear by about 15mm and the shifting is tolerable. there are of course, a few jumps in the cassette that are bigger then I would normally like in a push bike configuration, but the motor helps smooth that reality out in practice. One last note to doing this... you're likely going to need a longer limit screw for the derailleur to lock it out from blasting past the granny, and limit it to 7speeds.

I also clearance the motor housing slightly to get about 2mm back in the whole chainline system. I'm not currently running one of the 10mm - 42t narrow wide chainrings to get the chainline back even further. I'm just running the stock 5mm offset chainring. I'll be swapping to one of the custom offset nw chainrings this weekend to get that last little bit of shifting performance. Honestly, you could jump on this bike and you'd only know that the drivetrain was a cobbled together modified setup if I told you... it shifts just fine.

Clearance'ing the housing.

Before:
rJ3wRg5.jpg


After:
cwU8KUs.jpg


This frame requires some shims to avoid the housing touching the chainstay.
kxtUxXr.jpg


here's an eagle cassette on the bike without the chainline mods
wALXIIX.jpg


Laying the cassette out. this 11/46 SLX cassette is nice because it isn't riveted together, and the spacers are loose.
hLtLQva.jpg


The extra gears
8DnXcC4.jpg


Installed
RGTXYU8.jpg
 

Sgarth42

Member
Oct 13, 2021
73
51
York
Pretty nice builds here. I sorta disagree that these can be run without the temp capacity mods. I wouldn't bother with the temp sensor addition/mod on future builds, but I would opt to do the STO shim plate, cpu thermal grease between the flanges of the motor/stator, and pack the non-drive/dry controller side of the motor housing with either putty or thermal pads. It might just be my location and the fact that I'm huffing this thing up legitimate mountains and whatnot in 90 degree ambient (32c) temps often... but this thing will overheat pretty quick when putting out over 400watts on flat ground. Less so during actual trail riding as the load is so varied. One last notable thing with that... these stay cooler with a lower cadence. I have a pretty fast cadence as as pretty fit mtb rider to start off with (90+) and the FOC and resulting motor RPM, over 4,000, does cause these to build up heat faster then a 60-70 cadence and a motor rpm of 3,500-4,000. That seems like what is optimal for this motor.

Regarding chainline... that is the biggest drawback for these DIY mid drives, especially on modern boost frames. Any frame boost frame, particularly 29r made after about 2014 +/- that provide 2.4+ rear tire clearance, become difficult. I remedied this by making a 8speed drivetrain, based on 11 speed components and spacing. My trick to this was to use a 11-46 shimano SLX cassette, and to pull some of the cogs out. That cassette has the 3 largest climbing gears on an alloy spider, and then I pulled a few of the mid cogs out of the mix. this essentially allows me to improve the chainline in the granny gear by about 15mm and the shifting is tolerable. there are of course, a few jumps in the cassette that are bigger then I would normally like in a push bike configuration, but the motor helps smooth that reality out in practice. One last note to doing this... you're likely going to need a longer limit screw for the derailleur to lock it out from blasting past the granny, and limit it to 7speeds.

I also clearance the motor housing slightly to get about 2mm back in the whole chainline system. I'm not currently running one of the 10mm - 42t narrow wide chainrings to get the chainline back even further. I'm just running the stock 5mm offset chainring. I'll be swapping to one of the custom offset nw chainrings this weekend to get that last little bit of shifting performance. Honestly, you could jump on this bike and you'd only know that the drivetrain was a cobbled together modified setup if I told you... it shifts just fine.

Clearance'ing the housing.

Before:
rJ3wRg5.jpg


After:
cwU8KUs.jpg


This frame requires some shims to avoid the housing touching the chainstay.
kxtUxXr.jpg


here's an eagle cassette on the bike without the chainline mods
wALXIIX.jpg


Laying the cassette out. this 11/46 SLX cassette is nice because it isn't riveted together, and the spacers are loose.
hLtLQva.jpg


The extra gears
8DnXcC4.jpg


Installed
RGTXYU8.jpg
Thanks for the input. I guess I have been lucky as originally had 9 speed cassette and by good fortune the chainline seems pretty good. I certainly have no problems changing gears. I ride mostly trails so overheating doesn't seem to be a problem though I will be doing that mod at some point. If I was asked would I do it again. Yes definitely, I have learnt a lot in the process and enjoyed the challenges. It's not for everyone though.
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
Yup dropping a couple of gears is a good idea. But modern derailleurs and chains seem to be able to handle the offset caused by the motor. As long as you can get the 3rd gear in rough alignment, the 10 speed setups are good to go, the 9 speed is the same overall width and chain so no real gain there. 8 speeds are good for the road. We run 10 speed 11 -42’s pretty comfortably but need a Wolf Tooth “Goat Link “ if you want to go bigger on some of the frames.

The wider the rear tyre the frame can handle , the greater the chain line offset it would seem. Equally the later the frame the more risk you have of the suspension components getting in the way. My 2015 Whyte fitted no problem, the 2016’s won’t as they widened the rear triangle mounting points.

There are some mods such as 100mm and 120mm wide bottom brackets available if you have eg the later Trek frames but you can also take the grinder to the bottom bracket area and reduce the width, be careful though you are getting into possibly more than what most want to do.

On mounting the motor, we dimple the small left hand bracket with a centre punch to give it bit of anti twist grip ( Bafang do this from the factory ) against the BB. This together with tightening the nut with a mallet on the supplied spanner and there’s no need for any anti twist control on the likes of a full suspension frame. We had one bikes motor that kept coming loose, it was only when we realised that the motor was pulling up against the bottom stay when fully tightened and not fully the BB, it needed 1 of the supplied spacer shims to give clearance. That small brackets locating bolts need to be shimmed properly, we have seen some pretty odd angles there and it’s all too easy to strip the motor casing by trying to force the plate to bend to suit.

Best mods we have found so far for reliability are fitting good quality 2RS bearings in place of the dust seals on the chain ring spider and LH BB. The one thing we have yet to fully solve is water ingress, there’s a small casing hole for the torque converter wire on the top side behind the chainring side, it’s really high up and under normal conditions for which the motor was designed for, it’s not a problem. Here in the U.K. we stupidly ride in streams and mud, sadly we have seen small amounts of water and moisture eventually get into the internals. The main electrical controller is fully “ potted “ but will eventually fail along with the internal grease if you want to repeatedly ride in conditions way outside what the motor was designed for, Chinese commuter bikes.

Did you know Bafang have sold into the millions their BBS series engines and I would suspect Tongshen can’t be far behind. We here in the West are just starting to catch up.
 

Sgarth42

Member
Oct 13, 2021
73
51
York
Yup dropping a couple of gears is a good idea. But modern derailleurs and chains seem to be able to handle the offset caused by the motor. As long as you can get the 3rd gear in rough alignment, the 10 speed setups are good to go, the 9 speed is the same overall width and chain so no real gain there. 8 speeds are good for the road. We run 10 speed 11 -42’s pretty comfortably but need a Wolf Tooth “Goat Link “ if you want to go bigger on some of the frames.

The wider the rear tyre the frame can handle , the greater the chain line offset it would seem. Equally the later the frame the more risk you have of the suspension components getting in the way. My 2015 Whyte fitted no problem, the 2016’s won’t as they widened the rear triangle mounting points.

There are some mods such as 100mm and 120mm wide bottom brackets available if you have eg the later Trek frames but you can also take the grinder to the bottom bracket area and reduce the width, be careful though you are getting into possibly more than what most want to do.

On mounting the motor, we dimple the small left hand bracket with a centre punch to give it bit of anti twist grip ( Bafang do this from the factory ) against the BB. This together with tightening the nut with a mallet on the supplied spanner and there’s no need for any anti twist control on the likes of a full suspension frame. We had one bikes motor that kept coming loose, it was only when we realised that the motor was pulling up against the bottom stay when fully tightened and not fully the BB, it needed 1 of the supplied spacer shims to give clearance. That small brackets locating bolts need to be shimmed properly, we have seen some pretty odd angles there and it’s all too easy to strip the motor casing by trying to force the plate to bend to suit.

Best mods we have found so far for reliability are fitting good quality 2RS bearings in place of the dust seals on the chain ring spider and LH BB. The one thing we have yet to fully solve is water ingress, there’s a small casing hole for the torque converter wire on the top side behind the chainring side, it’s really high up and under normal conditions for which the motor was designed for, it’s not a problem. Here in the U.K. we stupidly ride in streams and mud, sadly we have seen small amounts of water and moisture eventually get into the internals. The main electrical controller is fully “ potted “ but will eventually fail along with the internal grease if you want to repeatedly ride in conditions way outside what the motor was designed for, Chinese commuter bikes.

Did you know Bafang have sold into the millions their BBS series engines and I would suspect Tongshen can’t be far behind. We here in the West are just starting to catch up.
Can the hole be sealed with a silicone sealer to help protect against moisture/water ingress?
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
Can the hole be sealed with a silicone sealer to help protect against moisture/water ingress?
Sadly no, it’s almost impossible to get to whilst assembling and that wire needs a certain amount of freedom, the torque sensor is mounted on springs and I feel if we lock the wire off, it will eventually break at the torque sensor.

The other factor is you need an air bypass hole to allow equalisation of air pressure as you go up and down hills, will blocking off the hole simply mean air laden with moisture is pulled into the motor through the seals with no way of escape when you arrive back down the other side of the hill.

A conundrum to say the least, but if you avoid riding across deep streams and avoid deep puddles ( I’m talking water levels up to and around the bottom of the motor ) then the motor does pretty well even in the muddy conditions of the U.K. winter.
 

Tooks

Well-known member
Subscriber
Mar 29, 2020
501
587
Lincs UK
I’ve got a couple of TSDZ2 conversions, both on old 26” MTBs that were languishing in the shed.

Both run the standard road legal 250w units, the full suspension one using a 36-42v battery made up from RC battery packs.

Although I’ve since purchased a factory e-bike, they still get a lot of use by friends and family, and they’ve been very reliable.

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AF68D9FC-FF78-4AED-89E5-6D04E05F5315.jpeg
 

Stharrison18

New Member
Jun 3, 2022
1
0
Usay
Absolutely. That bracket is actually a bafang BSBF-1 stabilizer mount (sourced through lunacycles BSBF-1 Stabilizer Bar for BBS02 and BBSHD). You end up having to do some re-bending of the mount and re-drilling the tabs to make it work with the TSDZ2 but it's not all that difficult. I've included a few more photos of it here so that you can see how I went about it. FWIW, I just templated it in card stock first, then cardboard before I went re-bending the mount in order to fit it to the bike. I specifically used this chameleon frame with this mount in mind because It had pre-brazed/mounted bottle cage bosses in the perfect location. In your case, I'd suggest worm clamps and rubber to mount the torque arm to the frame.

I can't believe i'm saying this, but I'm actually having a bit of a problem convincing myself to sell this bike, and or part out the kit. This thing will hammer along at 25mph with mtb tires on flat ground averaging 350w nominal without issue. It is definitely a pretty dang good setup provided you have the right expectations going in, I think most people would come out the other end quite content.

52mc5WZ.jpg


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zuRGbVn.jpg
Digging an old post up here but what does the black bolt do exactly? I’m fabricating a bracket for my bike now.
 

Sgarth42

Member
Oct 13, 2021
73
51
York
Digging an old post up here but what does the black bolt do exactly? I’m fabricating a bracket for my bike now.

I am assuming you mean the bolt at the back of the motor which is there to stop the motor rotating in the BB housing. It's not necessary if you tighten the crank ring bolt you very tight. I also rotated the motor forward onto the downtube (with some cushioning) so that it lhysically cannot rotate with the toruque from the motor.

20211207_203639.jpg
 

BLDC-ADDICT

New Member
Mar 1, 2023
2
2
Australia
So I've had a TSDZ2 On a 2009 Kona Stinky for over a year now with all the usual mods. Brass gear. Open source firmware temp sensor and cooling mods and have it blasting out 500W all day long. Such a great motor. Being a full suspension bike I was sending it everywhere especially as I seek out gravity riding. Only now am I concerned about the square taper spindle not holding up as I just converted to the 100mm BB extension for my new build with a 2017 Giant reign 1. I didn't realise the spindle was a weak point untill I was researching the conversion for the Reign. I've riden the bike a couple times hitting every jump and drop I can find, so fingers crossed it holds up as the motor is excellent. I did cram in a few more bearings to help with supporting the spindle .Having owned (for a brief time) a 2020 Giant Reign E+2 pro I'd have to say that I much prefer my current setup. The Motor as very similar performance to a commercial motor and in my current setup the bike weighs in 5kg lighter! Also batteries are a fraction of the cost to have a spare / replace. The Chain line is crazy though with the 11sp cassette but it does work. I have ordered a Shimano cassette to drop 3 gears as mentioned above. This info is greatly appreciated by the way. Hopefully the drivetrain will wear better as a result. I'm surprised that they didnt become as popular as the Bafang mid drives. But I guess the banfang BBSHD in particular is quite over engineed in comparison but the torque sensor with the TSDZ2 is what makes it great for actual off-road moutian biking. I hope all the info helps others with modern bikes as the bike is so my fun to ride with all the benifits of Carbon tubeless 650b wheels, big travel air suspension and modern geometry! Also a huge shout out to Sgarth42 for all the info provided on his trance build as the PF BB is the same on the Reign and alot of giant dual suspension bikes around that year.

20230224_150654.jpg 20230224_150606.jpg
 
Last edited:

Sgarth42

Member
Oct 13, 2021
73
51
York
So I've had a TSDZ2 On a 2009 Kona Stinky for over a year now with all the usual mods. Brass gear. Open source firmware temp sensor and cooling mods and have it blasting out 500W all day long. Such a great motor. Being a full suspension bike I was sending it everywhere especially as I seek out gravity riding. Only now am I concerned about the square taper spindle not holding up as I just converted to the 100mm BB extension for my new build with a 2017 Giant reign 1. I didn't realise the spindle was a weak point untill I was researching the conversion for the Reign. I've riden the bike a couple times hitting every jump and drop I can find, so fingers crossed it holds up as the motor is excellent. I did cram in a few more bearings to help with supporting the spindle .Having owned (for a brief time) a 2020 Giant Reign E+2 pro I'd have to say that I much prefer my current setup. The Motor as very similar performance to a commercial motor and in my current setup the bike weighs in 5kg lighter! Also batteries are a fraction of the cost to have a spare / replace. The Chain line is crazy though with the 11sp cassette but it does work. I have ordered a Shimano cassette to drop 3 gears as mentioned above. This info is greatly appreciated by the way. Hopefully the drivetrain will wear better as a result. I'm surprised that they didnt become as popular as the Bafang mid drives. But I guess the banfang BBSHD in particular is quite over engineed in comparison but the torque sensor with the TSDZ2 is what makes it great for actual off-road moutian biking. I hope all the info helps others with modern bikes as the bike is so my fun to ride with all the benifits of Carbon tubeless 650b wheels, big travel air suspension and modern geometry! Also a huge shout out to Sgarth42 for all the info provided on his trance build as the PF BB is the same on the Reign and alot of giant dual suspension bikes around that year.

View attachment 108142 View attachment 108143
 

Sgarth42

Member
Oct 13, 2021
73
51
York
Thanks - I hope you enjoy. You mention concern about the spindle on an extened crank and extra bearing is a must (though I see you have already done this). This is a weak spot arround the circlip groove and if you are using offroad, it will eventually shear (as I found out). Even on std 68mm BB it is still a weak area for seriuos MTB riding. However the good new is that there is a very quick, inexpensive & easy fix. Simply remove the dust seals on eaither side and replace with a sealed bearing outboard of the circlips. Simple but effective as it then supports the outer side of the axle past the shear point. If there is space, a thin rubber washer can be sandwiched over the bearing to help keep dust off but to be fair, they are easy replaced. Over 1.5k miles on mine now and still on original blue gear and I am running OSF 750w (though rarley ever use full assist). Hopefully this will be useful info for others though

20220704_154637.jpg 20220706_135701.jpg 20220718_155117.jpg 20220718_155125.jpg
 
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BLDC-ADDICT

New Member
Mar 1, 2023
2
2
Australia
Thanks - I hope you enjoy. You mention concern about the spindle on an extened crank and extra bearing is a must (though I see you have already done this). This is a weak spot arround the circlip groove and if you are using offroad, it will eventually shear (as I found out). Even on std 68mm BB it is still a weak area for seriuos MTB riding. However the good new is that there is a very quick, inexpensive & easy fix. Simply remove the dust seals on eaither side and replace with a sealed bearing outboard of the circlips. Simple but effective as it then supports the outer side of the axle past the shear point. If there is space, a thin rubber washer can be sandwiched over the bearing to help keep dust off but to be fair, they are easy replaced. Over 1.5k miles on mine now and still on original blue gear and I am running OSF 750w (though rarley ever use full assist). Hopefully this will be useful info for others though

View attachment 108164 View attachment 108165 View attachment 108166 View attachment 108167
Thanks again. I grabbed a couple 6902RS bearings yesterday and installed them. Now I guess I've done everything possible to prevent a future failure.. I'm waiting for 100mm Spindles to come back into stock at Eco Cycles as maybe I should keep a spare aswell.

20230303_162018.jpg
 

jaybee258

New Member
Mar 25, 2023
2
1
UK
Thanks - I hope you enjoy. You mention concern about the spindle on an extened crank and extra bearing is a must (though I see you have already done this). This is a weak spot arround the circlip groove and if you are using offroad, it will eventually shear (as I found out). Even on std 68mm BB it is still a weak area for seriuos MTB riding. However the good new is that there is a very quick, inexpensive & easy fix. Simply remove the dust seals on eaither side and replace with a sealed bearing outboard of the circlips. Simple but effective as it then supports the outer side of the axle past the shear point. If there is space, a thin rubber washer can be sandwiched over the bearing to help keep dust off but to be fair, they are easy replaced. Over 1.5k miles on mine now and still on original blue gear and I am running OSF 750w (though rarley ever use full assist). Hopefully this will be useful info for others though

View attachment 108164 View attachment 108165 View attachment 108166 View attachment 108167
Thanks - I hope you enjoy. You mention concern about the spindle on an extened crank and extra bearing is a must (though I see you have already done this). This is a weak spot arround the circlip groove and if you are using offroad, it will eventually shear (as I found out). Even on std 68mm BB it is still a weak area for seriuos MTB riding. However the good new is that there is a very quick, inexpensive & easy fix. Simply remove the dust seals on eaither side and replace with a sealed bearing outboard of the circlips. Simple but effective as it then supports the outer side of the axle past the shear point. If there is space, a thin rubber washer can be sandwiched over the bearing to help keep dust off but to be fair, they are easy replaced. Over 1.5k miles on mine now and still on original blue gear and I am running OSF 750w (though rarley ever use full assist). Hopefully this will be useful info for others though

View attachment 108164 View attachment 108165 View attachment 108166 View attachment 108167
That's a brilliant post . Thank you for all the detail. My crank axel has just snapped exactly the same. Where did you get your new axel from? I'm also-ran on the 100mm version and nobody seems to have that size. Many thanks.
 

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