this post was submitted on 03 Sep 2025

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Does anyone know whether this type of ebike frame to motor connection has a name? (lemmy.world)

submitted 1 week ago by python@lemmy.world to c/bikewrench@lemmy.world

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Sorry, might be a stupid question, I have literally no idea about bikes!

What I'm looking to do is figure out whether there are any modern-ish ebike motors on the market that I could swap my current motor with (I'm assuming I'd be swapping all the other innards to fit that motor too, so dw about battery compatibility and the like). All I know about the current Motor is that it's a 250W Panasonic motor from around 2011. I asked the mechanic at my bike shop whether I could just toss one of those Bafang conversion kits on the bike but he said the way that my pedals sit within the motor would be incompatible with that and I'd need to get an actual ebike motor, not a conversion motor.

So now I'm trying to find information on current Panasonic motors and what sort of frames they need to fit, but I'm having a hard time because I have no idea how to even call this kind of spacing on the frame. Does anyone have an idea on what to call it/describe it as? Or is is a proprietary thing that I'd need a welder to rework? (Totally an option if push comes to shove, I know a guy)

Some more pictures from as many angles as I could get into (should I be getting measurements of any of these?):

spoiler

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[–] psx_crab@lemmy.zip 1 points 1 week ago (1 children)

Hmm, agree with the other comment, it's a mid-drive, but yours seems to be fully proprietary, as in the bike frame made to be only compatible with the motor, and vice versa. I didn't even see a bottom bracket for you to convert it to normal bike, it seems like it's a one piece assembly.

If push come to shove, maybe you could use one conversion kit and make a bracket to fit the motor? If all else fail and you really love the bike, maybe turn it into front/rear wheel drive and gut the mid-drive to decrease the weight.

[–] python@lemmy.world 2 points 1 week ago (1 children)

I didn't even see a bottom bracket for you to convert it to normal bike, it seems like it's a one piece assembly.

I was thinking that maybe this part could have been a bottom bracket at some point (it's at least a hole that goes all the way through, no idea if it's stable enough to hold whatever it needs to hold), but seems kinda unlikely

I even found an archive of the Catalogue that my bike was sold in at the time hoping that maybe that frame was designed to be used for either an analogue or an electric bike, but it seems like only the electric bikes had that frame as an option 🥲

[–] psx_crab@lemmy.zip 1 points 1 week ago

If it's a tube and right size, it should have the strength for the crank. Though maybe you can fit one of those old style one piece crank if the size is right and you're going in that direction.

Something like this:

But from what i can see here, that mean the crank would need to move an inch or two up, might make the bike a bit hard to ride i feel like, since the bike is design to have that bottom bracket position right at the motor.

[–] litchralee@sh.itjust.works 1 points 1 week ago (1 children)

2011 is quite a while ago, and a lot of ebike technology has changed since then. Is there a particular aspect of this ebike which no longer meets your needs?

[–] python@lemmy.world 2 points 1 week ago (1 children)

I love the frame and overall ergonomics of the bike, but the motor is fairly weak and the batteries last maybe 10km per charge (plus they get pretty suspiciously hot when charging). With how much the technology grew in the past 15 years, it just seems like giving it a full refresh with a current-day motor and battery would be an easier choice than having to constantly hunt down original spare parts just to keep it somewhat alive, I think 🥲

[–] litchralee@sh.itjust.works 0 points 1 week ago

As the other commenters said, it'll be a difficult project to retrofit a replacement motor into a 15 year old frame. Not unless you or a friend can machine an adapter to fit.

From your post history, it looks like you're based in Europe. My brief understanding of Europe ebikes are that 250 W is the max continuous power, so if that's what this bike is still producing, I'm not sure if a replacement motor or even whole ebike would change that.

As for the battery, that might be worth replacing if possible, since the battery chemistry has definitely advanced. I'm a proponent of right-to-repair and making things last longer in general, so that's the route I'd take.

[–] ExtremeDullard@piefed.social 1 points 1 week ago* (last edited 1 week ago) (1 children)

I've always called this a mid-drive. They're quite common. I've installed quite a few of those motors from Cyclone in Taiwan and I recommend them.

[–] python@lemmy.world 1 points 1 week ago (1 children)

Oh, I thought mid-drive was just anything where the motor sits at the same place as the pedals, no matter how exactly it's connected. Do all mid-drive motors have a standardized layout on how they're bolted on? It would be quite nice if the existing bolt holes I have could fit just about anything haha

[–] ExtremeDullard@piefed.social 1 points 1 week ago* (last edited 1 week ago) (1 children)

They're anything but standardardized 🙂 In fact, that's why you choose them - either because your bottom bracket isn't designed for a motor, or your hub is special or something and won't take a motor either. Usually they come with universal bracketry, but most of the times you're better off getting creative to mount then.

Most of the ones I installed, I installed in my velomobiles because not much is standard in velomobiles either. I usually install a second chainwheel on the left-hand side by threading a new pedal hole in a right-hand side crank and mounting it in reverse, then I install a RHD mid-drive motor to drive the second chainwheel. That way, the regular transmission is totally unaffected. If I want to get really fancy, I also install a second derailleur in reverse to derail the chain off the second chainwheel on the left and totally disconnect the motor, if I want zero drag on muscle-power alone.

All of this is custom hackery obviously...

EDIT: here's an old video I made showing the left-hand side chainwheel and custom disconnector for the mid-drive motor:

https://www.dailymotion.com/video/x3bxatr

For your bike, I'm pretty sure you'll have to go down a similar creative path if you can't find original replacement parts. All that stuff looks custom OEM.

[–] python@lemmy.world 1 points 1 week ago

Makes sense, thank you for the thorough answer! I'll get some exact measurements of my bracket then and see how that compares to the layouts of the different motors out there ^^