Is possible to install bafang mid-drive motor on Strida?

Hello everyone,

I’ve been looking for ways to install a electric motor on Strida. I know that someone already did that with a friction drive motor, but i want a different type of motor, not a friction drive.

First i thought to install a hub motor, but my question is: Is possible to install a hub motor on a single sided axle? If is possible please tell me what tools and parts i need to do this conversion, and tell me if it is safe to do so.

If it is not possible to install a hub motor then i plan to use a bafang mid-drive motor named bbs01 or bbs02, the bbs02 is a little more powerfull.

But i need to ask some questions: Do you guys think the bbs01/bbs02 will fit normally in the Strida bottom bracket? Do i need to create or buy some adapter to make it fit? It appears from the pictures that strida have a strange/odd bottom bracket.

Let’s suppose that we have resolved the bottom bracket size issue. Now i need to know if it is possible to install a normal chain freewheel and use a normal chain to drive the wheel with the bbs01/bbs02 motor. If it is possible then i just need a bigger chainring to have chain clearance with the odd Strida frame.

If is not possible to install a normal chainring, i will need to use some form of adapter to attach the original strida beltring to the bbs01/bbs02 motor. It is not so hard to do. here a some examples of machined adapters, i just need to ask for a model that will fit the Strida.
( declic-eco.fr/boutique/accessoires ).

I’m waiting for your feedback.

Thank’s in advance.

Hello p4p4gaio,

in your first question you’re also answering yourself, guess you just overlooked the basic issue:

If you are able to find a single side mounted motor you could (maybe!) mount it on the Strida single side axle.
I’m writing maybe because you will have, even if you could find a suitable size, still the problem of the motor cables!
(There is no cable hole in the Strida frame - please don’t think of drilling one…)

You’re right, the Strida bottom bracket is unusual, I mean the BBS01/02 mounts will not fit, they’re intended for standard brackets.
Moreover that you must keep the function of the Strida excentric bottom bracket for belt tensioning; I’m quite unsure if this function would still work work with that type of motor mount.

Yes, it’s possible to use a (more or less) common freewheel and chain on Strida

  • for example the forum search (upper right corner) will show 133 results for “chain” :wink:

Our new chainwheel set for strida 5.0

Getting rid of the belt - how to retro-fit a chain ?

Hello Blackstridaaustria, Thanks for your help.

I made a search on google like this: “strida hub motor” and found some info, but can’t find a person that could sell the motor only, and regarding the torque force on a single axle, it can’t be a good option to electrify a strida.

So let’s go back to a mid-drive alternative.
I followed your links to a chain conversion and found it to be a good conversion and not so hard to do.
You said that the strida BB is “unusual” and the bbs01/bbs02 will not fit, but i need your expertise to know if it is possible to CNC machine an adapter to make the bbs01/02 compatible. Please, i’m not a bike mechanic/especialist and i don’t have a strida close to me to make any closer inspection, but i simply believe that is possible to make an adapter. Could you please help me to think into a solution to make a bbs01/bbs02 compatible with strida?

again, thanks for you help, i don’t want to bother you but i believe everyone will benefit from our ideas in this regard.

Hi p4p4gaio,
guess you mean the “info” about the Chinese front wheel drive which appeared years ago…

So you need some more details, well, here we go:

It’s not a matter of machining something by CNC or whatever, I mean it will be mechanically (or physically) impossible to fit the Bafang drives.
Yes, the Strida bottom bracket is not usual for several reasons:

  • Most likely it is narrower than common brackets (that’s an assumption!)
  • Anyway the diameter is bigger than usual (~ about 60 mm) - that’s fact.
  • Excentric bottom brackets, used for belt/chain tensioning purpose are extremely rare - prove me wrong.

You can find here
http://www.electricbike.com/bafang-bbso2-750w-mid-drive/
pictures of the drive, you will notice that there is less room between the bottom bracket and the motor case.
This distance is given by the construction of the drive - it is manufactured that way and can’t be changed by adapters.
If you want it different, you will have to create a complete new motor housing, including additional gears, shafts and bearings.

Assumed the drive would fit - the next issue:
The bolt on the underside of the Strida bottom bracket is implicitly required to lock the bracket, even if there would be enough room for the bolt 's head - how can it be moved?

You mean no problem?
Yes, it’s just required to move the bolt’s slot on the upper side of the bracket you might think

  • for sure a challenging task for an experienced metal worker…

So I’m indeed sorry, I can’t help you with a solution for the combination of Strida and Bafang.
Of course, if you need more, I’ll gladly try to explain my concerns better :slight_smile:

My logical recommendation must be this:
Either you should use another bike

  • or another drive.

However…I’d recommend also to go here:
http://www.endless-sphere.com/forums/index.php
Here are obviously real e-bike experts to meet, near nothing about Strida -
but you’ll surely find tons of articles about the mentioned Bafang drive.
The amount on collected knowledge is gigantic; guess you will need some time to select posts…
…anyway - if you find a possible solution and/or other things in that matter -
would you please let me know?
Feel free to use also the address below, thanks!

First, thank you for your great support on this question.
I’ve been looking at endless sphere forums for about 2 to 3 years, but mostly just viewing the works of others.
I tried to contact here first, because there are very few posts about strida on ES forums and probably few owners of strida bikes there, here i saw the first solution for e-Strida (the hiddenpower kit). But i think i will go back to ES forum to ask this question there.

You for sure have more knowledge about bikes than me, especially strida because you own one, and you too want a solution for electrify strida instead of a friction drive, So if you are saying that is not possible to install a bbs02 i simply cannot argue with you because of lack of knowledge. Thank you again, if i ever find a solution to this question i will contact you ok? Good bye.

Honestly, I’m a bit sad about your early good-bye…

Above said was meant if you insist on exactly Strida/BB02 combination,
but I think that’s not your main target - primarily you want a (preferred Strida)-bike with a mid-drive.
Maybe it’s possible to find another drive model which could be modified in an easy way?

Also, I don’t really understand why people with different points of view shouldn’t be able to argue constructive.
Actually, I mean it is very good to discuss contrary angles of sight - good chance for a touch of genius.
Please don’t overestimate neither my meaning nor “knowledge” - I’ll tell you some of the secrets which may lead to that impression:

  • Via Strida, I’ve found meanwhile several really nice and wise friends across the globe, in fact it is THEIR experience, THEIR inspiration and THEIR knowledge…all I try to do is to collect and share here.
  • Crawling through this forum for over four years will anyway increase your insight of Strida - automatically.
  • Working (for business) mostly mechanical since more than 30 years with an endless list of technical tools/devices, combined with much longer work (for fun) with - as above - and an inborn interest for anything which can be disassembled,
    such a life (OMFG…next birthday will be the 50!) will necessarily lead to some skills.
    And especially for you I’ll lift the curtain a bit higher:
    Would you believe that, back then, there was a little boy…his very first words were not “yes” or “no”…it were also not “Mom” or “Dad”…no, in fact his first words were “hammer” and “nail”…
    Few years later was Dad very, very angry - all I did was to disassemble the toy car which I’ve got for christmas :blush:
    Well, Ok, at that time I wasn’t able to reassemble it…more practice was required - definitely!

You maybe right with me and Strida (btw, that was incorrect - in fact I have three Stridas),
and I do know how to handle electricity - but in the area of e-bike drives I’m a noob (except the HP drive)!

On your place I’d not give up that easy, first I’d try to comprehend and prove your theory/claim.
I don’t want you to accept my meaning (possibly caused by fictive “competence” due to lots of posts), but I really want you to observe all given data/details closely - and finally draw your very own conclusions!

A hint out of practice:
Very helpful to imagine three dimensional relations are still - models!
Just rebuild the outer shape of the object (drive) with household materials (cans, paper, wood),
there’s no accuracy required, handling, searching and working with material will enhance your spatial sense immediately!
Sooner or later you will be able to imagine many things just by a drawing.

Not sure if you do already have this document;
bafang-central-motor-drive-system–bds01–feb-.pdf
I’ve used a drawing from page 6.
The red circle will be the approximately position of the Strida bottom bracket.

As you can see I’m still willing to support you, regardless the conflict of opinions :smiley:

This is the last step of the Bafang drive’s transmission

would there be chainwheels and a chain instead of the two gearwheels
then could the chances be better to make it Strida fit.
(A chain can be elongated easily, but not a gear drive.)

Maybe someone noticed a narrow mid drive with this kind of construction…