Folding mid drive conversion options?

[uhmwpolyethylene]

Maybe you could make this type of geometry even narrower by mounting the battery and all your junk to the front forks and putting the rear wheel closer to your butt or the front wheel closer. 2nd one is 12 inch. Im starting to see why folding bikes are popular though .

 

[uhmwpolyethylene]

The vello Montague style fold with intact front triangle could be cool but hard to tell if it could accommodate a mid drive. Montague made it work but people say changebike doesn't

 

[uhmwpolyethylene]

Seeing what is capable with a brompton and no hub motors kinda gives you an idea of what might be possible with a mid drive, straight outta brompton! .... I wonder how fast you could get at just removing and reinstalling a mid drive

I haven't installed one just ridden on one. I couldn't get concrete answers on the titanium brompton durability but I was watching a guy haul up Kathmandu on a steel brompton

 

[uhmwpolyethylene]

.

 

[17mph18a]

Might the Dahon Unio E20 work for the OP? Tongsheng Class 1 mid-drive with torque sensor PAS, small seatpost battery but 36lb light as a Brompton Electric.

 

[uhmwpolyethylene]

Might the Dahon Unio E20 work for the OP? Tongsheng Class 1 mid-drive with torque sensor PAS, small seatpost battery but 36lb light as a Brompton Electric.

the way this and the tern vektron are so cheaply welded with a wide bottom bracket mount dealie like those bafang ultra frames into what seems like a standard frame makes me wonder if there's really any danger using a bbs02, if not an HD. I was up last night feverishly thinking about how a dual hub motor brompton or Tern or cheap azz dahon/zizzo would actually scream too. Tern and Brompton seem to have the best safety record overall, the Tern fold hinge has a like 50/100 micron tolerance and stuff.

I wonder if you really had the time if something like this could just be removed from the whole system and put into your backpack-battery ala eBrompton. this is a 5000w motor and only weighs 7lb with transmission and controller, so you wouldnt even need that much. OUR MOTOR

 

[uhmwpolyethylene]

Might the Dahon Unio E20 work for the OP? Tongsheng Class 1 mid-drive with torque sensor PAS, small seatpost battery but 36lb light as a Brompton Electric.

here's an interesting dahon 16" one too. i'm a little skeptical about Dahon's safety record though lmao
the tern vektron has a bafang m400 or some bosch proprietary battery stuff, maybe m400 needs special batt also.
that dahon is also 2700$ and i cant find which tongsheng it uses yet or if it can take any batt

Dahon K3 Plus 9 Speed Folding Bike - Red - 16" Wheels | Default Title | Dahon North America

The K3 PLUS is designed for high endurance on your urban adventures. Evolved from the original K3 with an updated and sturdy frame geometry, the K3 Plus features 16" wheels and DAHON's patented Lattice Forged Hinge with ViseGrip technology. This showstopper’s 9 speeds, precision disc brakes and...

usa.dahon.com

 

[Chalo]

the way this and the tern vektron are so cheaply welded with a wide bottom bracket mount dealie like those bafang ultra frames into what seems like a standard frame makes me wonder if there's really any danger using a bbs02, if not an HD.

Why would there be any danger? They have any installed base probably larger than any other single type of mid-drive, and the worst that happens with them is they come loose and bang around a little. The ability to use almost any decent, industry standard bike frame beats marketing hogwash every time, if you ask me.

 

[uhmwpolyethylene]

Why would there be any danger? They have any installed base probably larger than any other single type of mid-drive, and the worst that happens with them is they come loose and bang around a little. The ability to use almost any decent, industry standard bike frame beats marketing hogwash every time, if you ask me.

yeah i just wrote bafang a diatribe telling them they're going in the completely wrong direction

the bafang m400 weighs like 3.5kg/ 8 lb already so I guess if the tern vektron is really just a "stock" tern frame with that dumb proprietary mid drive space another 1.5lb going up to the bbs02 might not be the end of the world. The HD though I wonder if another 3.5 lb is enough to cause some catastrophic failure, I guess if you mount the battery on a back rack you might get away with it. They claim the Vektron is ISO rated


might do some google fu on the dahon 16" max fork and rear clearance, too bad the crystallite saw20 is front hub only. (are there any other super narrow rear hub motors? Or other narrow front hubs?)

looking at the geometry of tern/dahon vs brompton it seems like it would actually be possible to mount a hub drive as mid drive... they dont really have the sexy fold of brompton and need a strap to even stay folded to wheel around too which is silly.

i keep coming back to the 16" scooter-bike or low double diamond platform with a big battery and mid drive and pedals mounted low... but that might be too low... Would be a game changer for so many people



i actually asked online what the max wattage of a scooter is before it becomes a moped but got no response, so that might be another advantage of scooter-bicycle vs scooter. but how to avoid this effect while still keeping it non folding...

 

[uhmwpolyethylene]

Mount an rc motor to the front fork for AWD without the wheel weight

 

[Chalo]

Mount an rc motor to the front fork for AWD without the wheel weight

Plus, the terrible racket will mask all the other noises your bike might make!

 

[E-HP]

Plus, the terrible racket will mask all the other noises your bike might make!

I saw this DIY ebike a couple of weeks ago, and it was surprisingly quiet. I had to get close before I could hear a light buzzing sound, but wasn't too irritating. Belt drive may have helped; plus she was riding at a very leisurely pace.

 

[Chalo]

Belt drive may have helped; plus she was riding at a very leisurely pace.

Belt drive can be silent at low speeds, but it gets howly at high speeds when the air entering and exiting the teeth gets worked hard.

 

[uhmwpolyethylene]

Belt drive can be silent at low speeds, but it gets howly at high speeds when the air entering and exiting the teeth gets worked hard.

i am curious if dyneema could make a good chain and cassette, or affordable handlebars and forks frame etc, it's self lubricating and absurdly strong, but has to be compression molded as a hard object with no room for error, and its uncertain whether you could like, thread screws and parts together, or links, because it is so slippery and unobtainiumesque, needs some exotic chemical to even glue to itself. it totally rejects moisture unlike kevlar also and has better UV resistance. however unlike the carbon belt drive you could probably have actual links and all that.

FRM has been doing a dyneema-carbon weave mtb
actually might make a great replacement for nylon cogs as well unless they really need to be sort of "soft". was reading about that PEEK gear but couldnt see what its made of. kevlar can resist like 800F though

could probably make a good Slingshot suspension type thing also. Youd really have to load it into FEA and see if it has any advantages over the double diamond. this one is done with kevlar. Some dudes in like hungary used idyneema for a weird drivechain but it looks really gimmicky and goofball Stringbike uses Plastic Instead of Metal Chains - Independent Plastic Oh and BERD Spokes and s-works shoe uppers of course. But that's thread, not solid plastic.

The Diverge STR gravel bike has this non-serviceable wear item thingamajig rear Future Shock

 

[Chalo]

i am curious if dyneema could make a good chain and cassette,

Not in this universe. It's a fiber.

Yes, there are carbon fiber composite chainrings out there. They suck.

or affordable handlebars and forks frame etc,

Sure, but it's just a synthetic fiber, like Kevlar, Spectra, Zylon, or even Nylon. It has pretty much the same benefits and tradeoffs as those, without the Young's modulus of carbon.

It's probably best as climbing rope or whatever flexible tensile material. Even the "transparent" kind is transparent like a stack of plastic bags, nothing you want to have to see through.

 

[uhmwpolyethylene]

Not in this universe. It's a fiber.

It can be compression molded as a hard plastic from powder, no? Like a milk carton or port a potty etc. Or layered panels/fiber panels for bulletproof plates.I met a guy using it for rockets. He was telling me molding it as a solid was obnoxious because if the results weren't good maybe you just have to chuck it all and can't recycle it.
I've only used it as a fabric yeah
It seems to weave well with carbon but it's so slippery I guess it maybe can't be woven like a nylon 66 Glock or how do they even do that. I guess FRM laminates it like a carbon fiber body anyway, and the fabric usually needs a polyester laminate backing to maintain strength, maybe with 30 percent polyester weave now also instead of weird slivers of pure
Maybe they'll figure out a way to remove the ice skating rink level of slipperyness, I doubt even a barbed texture would help, Paracord made of it has polyester sheath

 

[calab]

Stick with the tried and true for anything good or affordable.
No need to search the fields for the next best thing, its what the bicycle industry does, its how they make their profits.

 

[uhmwpolyethylene]

That superstrata Kickstarter for sintered 3d printed carbon was an absolute 100 percent disaster too. I'm glad the helix and chimera bikes are turning out ok. Sstrada raised like 5 mil and couldn't even support a person's weight with all the test photos ridden standing up, it was the Theranos of bikes

 

[uhmwpolyethylene]

Stick with the tried and true for anything good or affordable.
No need to search the fields for the next best thing, its what the bicycle industry does, its how they make their profits.

Too bad bafang is already moving towards proprietary, because there's literally an endless supply of aluminum MTBs and steel road bikes sitting in garages across the world except the 90s rigid MTBs those are 600-800$ now

 

[calab]

In March 2023 there was an auction of 35k bicycles from company that not doing so well, they claimed a total value of $25m but what did they really get for all those bikes. Auctions are online so many would buy without seeing it first.
90's mtbs are cheap, no one wants to buy a used bike, they want new even if its a shitty bike from Walmart then buy a used bike that is 100 times better then the Walmart crap. Its just that they cant do stuff with their hands, so they have to pay someone to fix their old, dirty bike. Cost of repair is more then a Walmart bso.

 

[uhmwpolyethylene]

1kW Front Hub Motor on Cheap Chinese Folding Bike Post in thread '1kW Front Hub Motor on Cheap Chinese Folding Bike'

Lol

 

[17mph18a]

i cant find which tongsheng it uses yet or if it can take any batt

It's difficult to identify which motor from the Tongsheng product page, but from the position of the axle it looks like a custom shell for Dahon around a TSDZ10, detuned to 200w/60Nm. The battery seatpost on the Dahon Unio is the same width 57mm as that used on the Qualisports Dolphin, however Dahon have added a power-on button on top of the Unio seatpost which is absent from the Dolphin seatpost so the pack may not be interchangeable. A couple of useful additional accessories for the Dahon Unio would be a clamp lock and maybe a Tern Porter+ saddle for lifting the bike unfolded.

 

[17mph18a]

The Bike Friday Pakit has a front hub motor option that should work with any 36v battery, and lightweight at 29lb with their 230wh battery. BF use Grin Tech for their electrical systems, though it's unclear to me what hub motor and controller combination they are currently using. Like Brompton it has 16" wheels and the rear frame folds under the bike.

 

[uhmwpolyethylene]

Heh, went searching for long wheelbase foldable uprights and found this gem

Folding Linear Limo Recumbent Bike

Folding Linear Limo Recumbent Bike. A longwheel base recumbent bike that folds to make it easy to transport. Made in the USA!

linearrecumbent.com

 

[calab]

It looks real comfortable.

Montague folder I'd trust for a hub or mid drive, but max of 500-750w 36 or 48/52v. That extra powers for the hills.