ebike Kit for Cargo bike with torque sensor?


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1:38 PM
Jul 24, 2020

I have been doing some searching but have not found what I am looking for "yet".

I have a heavy cargo bike and would like to retrofit this thing with electric assist.

However, I would like this set up to be like what an ebike does in that it senses input torque and assists accordingly. And are there any other companies out there that have systems that work like this?

Is there anyone making stuff like that out there? I know I read Bosch was coming out with a system that works/acts like that but it's not retrofitable to a current bike as I know it. Theirs requires a specific frame.

Thanks so much,
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What you need is a BBSHD.

No torque sensor though. Big whoop, my thumb is a much more sensitive and responsive way to supply any needed assistance then any other way I have tried.

Throttle:it's not a 4 letter word! Over and over here, I see the off hand dismissal of a throttle on an ebike as totally unacceptable, even from those who ride ebikes but somehow think their PAS systems are "purer." The BBSHD has the cadence sensor and the thumb throttle, simple, works great, and readily available, cheap also.

Before I get slammed for bringing this throttle thing up (and I will....that's cool) you non ebikers realize that having one does not mean you don't pedal, right? It seems like having one means you don't, ever, and I know you love to insinuate that every chance you get, BS! When I ride my steep and rocky trails around here (relax, fully compliant and legal) the thumb throttle is the way to augment any power assist I feel the need for, and I sure as hell don't apologize for it. The reason I go into the subject, is if you are looking for a torque assist system, with no throttle, because you think it's somehow more purer and makes you more a real mountain biker, fine, but after a couple thousand miles of trail riding I am keeping my 10 level cadence sensed PAS system AND my thumb throttle. Get ready to spend the big bucks on a factory bike, to answer your question.
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A BBSHD as mentioned or the smaller BBS02 are good choices but you're stuck with a PAS cadence sensor. If you appreciate torque-sensing PAS you won't like cadence PAS.

There are several choices for DIY torque sensing PAS but you'l probably need to cobble together a system. Not too hard if using a hub motor but if you want a mid-drive with a torque sensor then you need a torque sensing crank assembly and they ain't cheap. And you'll need a controller sophisticated enough to be programmed with PAS input.

A good place to start is Luna Cycles for most of the system and Grin Technologies for other bits and pieces like the torque sensor.
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OK. Thanks you guys. Appreciate the responses so far. I have ridden both types and do prefer the torque sensing. And no, I don't judge you or others as it's your choice and I'm cool with that. And why I posted this query here to see if anyone has something at the moment. Thanks so much for the info.
I'd just use a throttle system too. Much cheaper, easy to deal with, and it'll do exactly what you want when you want it.

I've had a couple of cargo bikes. Sold them both since they were just a pain to use when loaded. Definitely needed assist.
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Hub motors do not tend to be high torque motors although some are wound to be better than the run of the mill cheap China hub for climbing or sustained high output. There are geared hub motors, but the jury still seems to be out regarding the longevity of the plastic gears. There are really no plug and play mid drives with torque sensing except the TSDZ2 which is very low powered. You could go down the route of a BBSHD with a PhaseRunner controller and a torque sensing PAS system, but that can become quite the science project!
I use a Bionx motor on my Surly Big Dummy cargo bike. I'd highly recommend it, except that they are now out of business...

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As noted above, BBHSD from Luna Cycle. I recently put a Luna BBHSD kit on a Kona Minute. It is so fun to ride. The throttle is great when you want it, but the pedal assist works really well also with the power switch to modulate speed and power. The motor is practically silent and has lots of power. My wife doesn't really use the throttle, I sometimes do. We mostly use the pedal assist.

This kit has serious power. I live on a very steep hill and it'll go up it with me and another adult on the back at 10+mph. It'll go 34mph on a slight downhill and easily do 25mph on the way back up.

It has made running into town by bike a real pleasure, for errands, kid pick up or drop off, or grocery runs.

Read some on the Luna site and it's associated forum. There is a lot of info on there.
I don't have a problem with throttles, standard bikes or PAS as long as the rider is responsible. If there are hikers, families or animals about we have to ride responsibly that's more my concern.