Surly ECR and BAFANG BBS02 48V 750W Mid Drive Kit

[RickUrb]

I'm thinking about converting my 2020 surly ECR to electric.
My first inclination is to go with what Jone's Bikes is putting on theirs, Bafang mid drive.
I'm specifically thinking of the BAFANG BBS02 48V 750W.
It's half the price of the 1000 and I think it may get me by. A heavy rider, but I don't ride fast. I like to take it on gigs and I would probably need to get about 60 miles out of it.
also, I’m not sure if their batteries are UL approved. Any idea? It’s kind of a big thing with me.
Any other ideas on manufacturers to look at? The only thing about Bafang is it seemed, judging by the videos, that it wasn't the best build quality. But I am new to this and looking for input.
Thanks much

 

[amberwolf]

I'm thinking about converting my 2020 surly ECR to electric.
My first inclination is to go with what Jone's Bikes is putting on theirs, Bafang mid drive.

As long as you already know the drive will fit your bike, as there are various BB standards, frame designs and shapes, and the various middrives will only fit a limited selection of these.

If you're not sure a drive will fit your frame, you may have to look up the drawings and measurements of the drive, and compare those to your actual frame. (different model years of a frame may have different shapes/etc).

I'm specifically thinking of the BAFANG BBS02 48V 750W.

It's half the price of the 1000 and I think it may get me by. A heavy rider, but I don't ride fast. I like to take it on gigs and I would probably need to get about 60 miles out of it.

There are a number of things that affect performance of a system, so your best bet to be certain a particular drive will do the job you want is to first completely define the job and all of the worst-case conditions it has to do that job under, including your specific terrain, wind, road conditions, riding style, etc, and then take those to one of the various online calculators or simulators like the ones at ebikes.ca, and use all the info to create guesstimates of the total power you need to do the worst parts of the job (which is how much power the system as a whole must be able to provide, including battery, controller, and motor), and of how much power it uses over time to do various parts of the job (which helps determine how big a battery you need to get the range you want).

also, I’m not sure if their batteries are UL approved.

To actually find out if something is UL listed, you would need to check with UL themselves, because so many companies lie about all sorts of approvals, with labels on their products indicating such when they never even attempted to test things to the standards, much less go thru the actual process.

I've not checked, but I expect only a handful of ebike batteries available to end-users are *actually* UL-listed. Most OEM complete-bikes' batteries probably aren't, either.

Any other ideas on manufacturers to look at? The only thing about Bafang is it seemed, judging by the videos, that it wasn't the best build quality.

If you haven't already, you can read around the many threads about the various middrive (and hubmotor) systems available to better judge quality, by seeing what kinds of problems repeatedly crop up (and which are one-offs or not caused by design/manufacturing but rather by end-users). There are some big threads about each drive that have the most information in one place, and lots of little ones about specific builds, problems, DIY stuff to upgrade them, etc.

 

[BicycleJoe]

I was planning to add a mid-drive motor to a Surly (BBSHD-Karate Monkey) but the wide drive-side chain stay changed my mind. Surly bottom-bracket shells are quite narrow relative to the width of that flat steel chain-stay yoke. For my install, the chainring would be so far outboard that only the smaller cogs would be usable. Your ECR may work with a BBS02. The best way to know is to print the install-template Here: BBS02 & BBSHD Motor Fitment Templates | BafangUSAdirect Help Center

Print it to correct scale and cut out with scissors. Slide it into the BB shell to see what chainrings will fit and how much you have to shim the motor out. It looks like this, but don't print it from here, must print to scale.

edit: The template below is for the BBSHD. It's my understanding that the BBS02 is more forgiving with chainline. The correct template is posted at the link above.

 

[RickUrb]

I was planning to add a mid-drive motor to a Surly (BBSHD-Karate Monkey) but the wide drive-side chain stay changed my mind. Surly bottom-bracket shells are quite narrow relative to the width of that flat steel chain-stay yoke. For my install, the chainring would be so far outboard that only the smaller cogs would be usable. Your ECR may work with a BBS02. The best way to know is to print the install-template Here: BBS02 & BBSHD Motor Fitment Templates | BafangUSAdirect Help Center

Print it to correct scale and cut out with scissors. Slide it into the BB shell to see what chainrings will fit and how much you have to shim the motor out. It looks like this, but don't print it from here, must print to scale.

edit: The template below is for the BBSHD. It's my understanding that the BBS02 is more forgiving with chainline. The correct template is posted at the link above.

View attachment 335962

That is some invaluable, awesome information there. Thank you very much!