Mid drive torque sensor

#1
Hello,
I'm looking at buying an ebike kit. I'm not sure what to buy. I'll probably put it on a bike that I'll build up from spare parts. Do any mid drive kits have torque sensors? I hear they make it smoother. I'm also looking for pedal assist, not a throttle. I'd like a 28mph speed. It's also hilly where I live so I hear mid drives are better for that.

Thanks
 
#2
Hello,
I'm looking at buying an ebike kit. I'm not sure what to buy. I'll probably put it on a bike that I'll build up from spare parts. Do any mid drive kits have torque sensors? I hear they make it smoother. I'm also looking for pedal assist, not a throttle. I'd like a 28mph speed. It's also hilly where I live so I hear mid drives are better for that.

Thanks
I've only seen torque sensors available for hub drive kits. Most kits have a throttle, but its optional to install if you just want pedal assist. A Bafang BBS02 would have no problems reaching 28 mph with pedal assist. Mid-drives do climb better when comparing hub motors with similar outputs. That said, once you get up to 1000-1500 watt hubs, hill climbing is just as effortless.
 

harryS

Active Member
#5
The new Bafang "Ultra" mid drives do have a torque sensor, but are intended for OEM bike manufacturers. A home builder would likely need aluminum welding capability as I assume they use a aluminum motor frame.

There is a mid drive kit for the home builder, the Tong Sheng TDSZ2, with a torque sensor. It has no throttle. While you can buy the Bfang BBS02 and BBSHD from US importers with inventory here and some spare parts, the Tong Sheng must be ordered direct from China, although you can buy it via amazon and have their backing. Here is a link to very long thread from users. I am intrigued by them, but already have a BBS02.

Maybe I haven't noticed, but I've never seen a post from a Bafang BBS02/BBSHD owner complaining about the lack of a torque sensor. Probably seen more posts from OEM mid drive owners lamenting the lack of a throttle. Just my opinion, my BBS02 is pretty smooth when pedaling, but of course I have to settle for what I got.

Still, if you want to go really faster, the 1000W BBSHD will let you do that,and it probably will keep doing that while my BBS02 and the Tong Sheng have melted the motors. Not kidding here. OEM bike makers use thermal sensors to shut off hot motors. These will run til you melt the nylon gears.
 
#7
Just my $.02. I am an ebike technician and builder of custom ebikes. I have ridden almost everything in the ebike world. I own several BBSHD's and for my money I would buy another. Pedal assist and throttle, no torque assist. I my opinion torque assist is highly overrated. I've ridden the Bosch Haibike and the Bulls bikes. I find I prefer the pedal assist, and I wouldn't have a ebike without a throttle, to many times that instant full acceleration can save you in traffic. Not only that but a throttle makes hills melt away. I live at the top of a 22% grade, after a 50 mile bike ride it sure is nice to hit the throttle and fly to the top! Also there have been many reports of reliability issues with both the BBS02 and the Tong Sheng when used on big hills with heavy loads. I've yet to kill a BBSHD!
 
#8
Just my $.02. I am an ebike technician and builder of custom ebikes. I have ridden almost everything in the ebike world. I own several BBSHD's and for my money I would buy another. Pedal assist and throttle, no torque assist. I my opinion torque assist is highly overrated. I've ridden the Bosch Haibike and the Bulls bikes. I find I prefer the pedal assist, and I wouldn't have a ebike without a throttle, to many times that instant full acceleration can save you in traffic. Not only that but a throttle makes hills melt away. I live at the top of a 22% grade, after a 50 mile bike ride it sure is nice to hit the throttle and fly to the top! Also there have been many reports of reliability issues with both the BBS02 and the Tong Sheng when used on big hills with heavy loads. I've yet to kill a BBSHD!
I can appreciate you have your preference. Thing is, many jurisdictions are going the route of pedal assist only. It seems that the line is getting drawn at whether you have to pedal or not. Where I live, ebikes with a throttle are not allowed on pathways.

When you say you prefer the pedal assist vs torque sensing, do you mean the cadence sensor that the BBSHD uses? I'll admit, I haven't tried one. So far I've only ridden bikes with the typical Bosch, Brose, Yamaha integrated motors, and the Tongsheng kit I installed on the Mundo.
 
#10
I can appreciate you have your preference. Thing is, many jurisdictions are going the route of pedal assist only. It seems that the line is getting drawn at whether you have to pedal or not. Where I live, ebikes with a throttle are not allowed on pathways.

When you say you prefer the pedal assist vs torque sensing, do you mean the cadence sensor that the BBSHD uses? I'll admit, I haven't tried one. So far I've only ridden bikes with the typical Bosch, Brose, Yamaha integrated motors, and the Tongsheng kit I installed on the Mundo.
No throttle allowed. No problem, it doesn't have to be installed. And Yes, the cadence sensing is what I refer to as pedal assist. I have found that the preference for one or the other (cadence vs torque) falls into two groups. Young and athletic seem to prefer torque sensing, older and less athletic prefer cadence sensing. Everyone loves the throttle!
 
#11
No throttle allowed. No problem, it doesn't have to be installed. And Yes, the cadence sensing is what I refer to as pedal assist. I have found that the preference for one or the other (cadence vs torque) falls into two groups. Young and athletic seem to prefer torque sensing, older and less athletic prefer cadence sensing. Everyone loves the throttle!
Interesting. I was under the impression that cadence sensor only for pedal assist wasn't very good. I had just about gone the Bafang route without throttle before I came across the Tongsheng kit. Hopefully I'll get a chance to try one out sometime. Thanks for the info.
 

harryS

Active Member
#12
Getting back to Triboiler, where a torque sensor helps is when someone starts off in the wrong gear from a stop and a mighty press on the pedals is needed. The pedals need to move at least 1/4 turn on some cadence sensors, so it's going to be the rider moving the bike to get started, unless there is a proper torque sensor, which will sense the foot pressure and start the motor. A cadence sensor is out of luck here.

This happened to my wife last summer when we had to ride up a hill from a start. She was in high gear, couldn't move, and fell over. I explained to her, if she wasn't going to downshift, she could start off with the throttle. The throttle used to scare her. Now it's her friend. She rides geared bike motors, which always have enough torque to start in most situations.

Now if you are riding your spiffy Bosch mid drive up a big hill in a gear so high that you cannot pedal, you still might stall out and fall over if the gear is too high for the motor. The engineers cannot make the biking experience idiot-proof, not until we get automatic transmissions. Personally, I love the feel of a well tuned, good shifting bike and walking up and down the gears is fun for me. So I'll be in the proper gear and ready to go. Don't need motor or throttle.

If one sets a cadence sensor in the highest assist level, you can ride with no effort or feel, but there's no fun or exercise in that. On my bikes, the motors cuts out at a given rpm associated with each assist level. So when I pedal above that speed, I'm doing most of the work, and it's just like a regular bike to me.
 
#13
^ Oh gawd, I'm always giving my wife crap about not shifting down and trying to start again on a high hear. Drives me nuts. After I upgraded the thing to an ebike, I keep telling her she's going to break something. I'll be replacing chains pretty frequently on it.
 
#15
Just my $.02. I am an ebike technician and builder of custom ebikes. I have ridden almost everything in the ebike world. I own several BBSHD's and for my money I would buy another. Pedal assist and throttle, no torque assist. I my opinion torque assist is highly overrated. I've ridden the Bosch Haibike and the Bulls bikes. I find I prefer the pedal assist, and I wouldn't have a ebike without a throttle, to many times that instant full acceleration can save you in traffic. Not only that but a throttle makes hills melt away. I live at the top of a 22% grade, after a 50 mile bike ride it sure is nice to hit the throttle and fly to the top! Also there have been many reports of reliability issues with both the BBS02 and the Tong Sheng when used on big hills with heavy loads. I've yet to kill a BBSHD!
Agree,Agree with the throttle. Could literally save your life in the right situation. Rick , could you recommend a nice geared hub motor for a women's crank forward bike. It would be ridden by both girl and guy in State parks and campgrounds. 20 - 25 mph plenty. Would need to climb some small to moderate hills. Thanks !
 
#16
Hello Tom! I think you will find just what you need at Grin Technologies. I would recommend this:

http://www.ebikes.ca/shop/electric-bicycle-kits/geared/front-mini-geared-kit-advanced-pas.html

But you might want to look around at some of their other hubs, both geared and direct drive.
Whichever way you go I would recommend a front mount, unless you have a suspension fork. Installation and tire changes are much easier!
A good direct drive option is this:

https://lunacycle.com/smart-pie-v5-golden-motor-hub-kit/

Be cautious about no name Chinese hubs which are popping up online everywhere. Stick to well known makes like, Golden motor, Crystalyte, TDCM, Nine continent, Bafang or Ezee.
Good Luck!
 
#17
After a half dozen BBSxx drives I went to front drive MAC. Although ordering a new rear Mac for 2wd finally!
Front drives have their plac3 and have a bad rap. I ride on mostly flat streets and theyre great. Id l8ke an EXee but $$$
 
#18
Hey Tom Jaszewski! How have you been?! Judging from the time of your post, your sleep pattern is as erratic as mine! Oh well, I guess us old guys sleep when we can, and talk ebikes the rest of the time! I agree front drive hubs are a great way to go! Makes the install and tire changes a snap compared to rear mount. Glad to hear your 2wd is coming along, I have often considered doing one myself! Might be happening soon, especially if the 'new' BBSHD firmware is here to stay. Don't know if you have heard, but a lot of people that got a BBSxx recently have found that the throttle won't work if your pedaling!! Luna says it's a permanent firmware change and there is nothing to be done, then they say they have a fix. Same old double talk, some things never change! Then some do! I bought 10 BBSHDs from Paul @ EM3EV, only one had this problem and he replaced the controller under warranty. Still trying to find out if this is really a Factory intentional change or an error in production. Hoping it's an error and corrected soon, or I'll be looking for a different mid-drive. Or building a lot of hub drives! You have always been well connected in the ebike community, have you any news?

My bad! I should have included the Mac in my list of quality hub motors. One of the best for the money!
 
#19
Hey Tom Jaszewski! How have you been?! Judging from the time of your post, your sleep pattern is as erratic as mine! Oh well, I guess us old guys sleep when we can, and talk ebikes the rest of the time! I agree front drive hubs are a great way to go! Makes the install and tire changes a snap compared to rear mount. Glad to hear your 2wd is coming along, I have often considered doing one myself! Might be happening soon, especially if the 'new' BBSHD firmware is here to stay. Don't know if you have heard, but a lot of people that got a BBSxx recently have found that the throttle won't work if your pedaling!! Luna says it's a permanent firmware change and there is nothing to be done, then they say they have a fix. Same old double talk, some things never change! Then some do! I bought 10 BBSHDs from Paul @ EM3EV, only one had this problem and he replaced the controller under warranty. Still trying to find out if this is really a Factory intentional change or an error in production. Hoping it's an error and corrected soon, or I'll be looking for a different mid-drive. Or building a lot of hub drives! You have always been well connected in the ebike community, have you any news?

My bad! I should have included the Mac in my list of quality hub motors. One of the best for the money!
Bafang....typical. Yeah we've been getting frustrated buyers. I wonder if they will ever become responsive. Imagine being the biggest reseller and STILL not getting good intel! I sold the last BBSHD I had and all the parts with it. I had collected every replacement part when I thought I'd be keeping all 3. It was time for a change. But we still use the two BBS01's for riding on the paved bike/skate/walking paths. No need for speed and power there. Yeah crazy sleep pattern is right! The joys of being retired!
 

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