Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

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lokz   10 µW

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Joined: May 18 2021 3:11am

Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by lokz » Jun 03 2021 2:59pm

Hello,

I need help finding some kit within EU or China, since mid drive TSDZ2 does not fit and BBS02 is cadence based only.
My bike:
https://www.cube.eu/en/2016/mtb-hardtai ... lack-2016/

Frame 21", wheels 29"

First, I want to know what is optimal engine power for pedal assisted MTB rides. I want to pedal, I enjoy that sport, but for longer mountain trips I need some assistance. 350W?, 500W?
I aim for geared hub drives, light as it can be, with as less resistance on pedals when not using motor power.

Next, is there any EU based company that can help me find the best option for my bike and sell me that kit?

That is all for the start, please write your opinions, advices.

docw009   1 MW

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Location: Chicago area suburbs.

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by docw009 » Jun 05 2021 9:25am

Doubt there are many T/S rear hub kits. Torque sensing is an over rated biking experience in my opinion, when I test rode them a few years ago, I have yet to install my TsDZ2, but plan to do it soon.

Most of our hub motor ebike conversions use KT torque simulation controllers. This is basically current control on the pedal assist. Works smooth and if one picks the appropriate level, seems pretty natural to me. One can program the controller for a specified amount of watts in level 1, and it increases with level. Setting 80 -100 watts in level 1 makes for a fairly natural pedal feel. Yes, if the bike is moving, you can spin the pedals lazily and the bike runs w/o effort, but the idea is to go faster and pedal at the top of the power range for that level, and then you and the motor will share the work.

ALso have a Bafang BBS02, and while their PAS is cruder, it doesn't feel artificially boosted, as there are 9 levels of assist.

However, you can buy a torque sensing BB from Grin ebikes in Vancouver, Canada, add their cycle analyst display, and for about $200-250 USD, plus shipping, it will convert your pedal torque to a voltage for the throttle input on your controller. I'm not that much of a cycling purist that I want to add $250 to the $100 worth of electronics on my bikes.I hear it works great though.

ATinkerer   10 mW

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Location: Port Angeles, Washington State

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by ATinkerer » Jun 05 2021 12:58pm

Used Grin's bottom bracket torque sensor combined with CA on my Scorpion ebike conversion.
Works well with geared hub motor I chose to use and phaserunner.
If it's not broken, fix it anyway.

lokz   10 µW

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Joined: May 18 2021 3:11am

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by lokz » Jun 06 2021 1:30pm

Do they sell whole conversion kits or only BB TS?
ATinkerer wrote:
Jun 05 2021 12:58pm
Used Grin's bottom bracket torque sensor combined with CA on my Scorpion ebike conversion.
Works well with geared hub motor I chose to use and phaserunner.

lokz   10 µW

10 µW
Posts: 5
Joined: May 18 2021 3:11am

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by lokz » Jun 06 2021 1:34pm

BBS02 would fit to my bike. I read its build quality is better than TSDZ2.
The reason I am trying to convert my bike to eBike is extra assistance uphill. I still want to pedal a lot, because that is bikes are for.
But years are catching, I cannot pedal as I could 5-6 years ago.
I would go for Bafang BBS02, but I am afraid that cadene sensing will not be as great feeling as riding regular bike, if you know what I mean.
docw009 wrote:
Jun 05 2021 9:25am
Doubt there are many T/S rear hub kits. Torque sensing is an over rated biking experience in my opinion, when I test rode them a few years ago, I have yet to install my TsDZ2, but plan to do it soon.

Most of our hub motor ebike conversions use KT torque simulation controllers. This is basically current control on the pedal assist. Works smooth and if one picks the appropriate level, seems pretty natural to me. One can program the controller for a specified amount of watts in level 1, and it increases with level. Setting 80 -100 watts in level 1 makes for a fairly natural pedal feel. Yes, if the bike is moving, you can spin the pedals lazily and the bike runs w/o effort, but the idea is to go faster and pedal at the top of the power range for that level, and then you and the motor will share the work.

ALso have a Bafang BBS02, and while their PAS is cruder, it doesn't feel artificially boosted, as there are 9 levels of assist.

However, you can buy a torque sensing BB from Grin ebikes in Vancouver, Canada, add their cycle analyst display, and for about $200-250 USD, plus shipping, it will convert your pedal torque to a voltage for the throttle input on your controller. I'm not that much of a cycling purist that I want to add $250 to the $100 worth of electronics on my bikes.I hear it works great though.

docw009   1 MW

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Posts: 1900
Joined: Aug 02 2015 7:43am
Location: Chicago area suburbs.

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by docw009 » Jun 06 2021 5:18pm

Yes, Grin sells complete kits, but they're too expensive for me.

ATinkerer   10 mW

10 mW
Posts: 20
Joined: Jan 11 2020 4:52pm
Location: Port Angeles, Washington State

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by ATinkerer » Jun 07 2021 11:10am

Your choice. Grin will sell component parts, or a coordinated kit.
As the other poster mentioned, they are not cheap.
Compared with complete ebike purchase, could be considered inexpensive, if you have the talent to assemble, program and test what you select.
If it's not broken, fix it anyway.

MikeSSS   1 kW

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Location: San Antonio, TX

Re: Rear HUB drive kit with torque sensor (bottom bracket), Bafang, Tongsheng

Post by MikeSSS » Jun 07 2021 6:51pm

Pedal power and throttle assist power work really well together. Pedal power along with throttle and cruise control power work even better together.

Torque sensor pedal power along with throttle power worked very well on the Bafang Ultra mid drive bike I rode.

Pedaling sensor, either rpm or torque, is not needed, I just pedal hard as I want at the moment and use the throttle to give the speed I want.

Again, throttle with cruise control and pedaling as hard as you want at the moment works best.

Cycle Analyst V3 is just fine for this.

Cruise control lets you leave the rear derailleur shifter on the right side, rather than moving it to the left where the front shifter is.

Hope this helps.

PS, rpm pedal sensor is just wrong because it's counter intuitive.

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