Folding mid drive conversion options?

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.
Funny enough Montague is not iso rated but changebike and tern are, I guess changebike doesn't work with mid but the Tern 26" folder has a split frame https://www.ternbicycles.com/en/bikes/471/eclipse-x22 . ... Montague sells a heavy mid drive ebike.

Messing with astro rc motor and stuff, wat do you call this anyway, "rc motor as mid drive "... Are there downsides to this? If a 5lb motor does 5000w... Can a 1 lb one do 1000w lmao. The transmitter weighs another 2 and another video shows it's assembly

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.75lb 1200w skateboarding motor. 1000W 200KV 12S Outrunner Brushless Motor for Skateboard

I think someone had a post recently says why this isn't so simple to do
 
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i told myself i wouldnt lose it, but theres an article somewhere about a failed italian bike made from collapsable rope connected to tension hubs or whatever. i had similar idea but using less crappy rope. integrated suspension! tensegrity! hey berd is doing it...
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met a guy who worked on a car held together with magnetism but it wasnt really crash safe. for a bike it might make sense for a suspension joint or something like a moulton.


Oh I saw one of those DAHON 2-fold folders today! Was pretty nice. think it had 14" wheels though, same model name diff sizes...
 
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HMMMM rc motor here?
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nice little part to make the cheaper bromptons rollable with the seat like the P-line as well Fold Retainer 2 for Brompton - 3dbikemods
 
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eh friction motor but kinda interesting "The entire thing weighs less than 1 kg plus the battery @ 626 grams."

a partially water sealed e skateboard motor 6354 190kv Motor 2450 Watts

where is the big discussion here on using RC/drone/type motors like chimera, and the disadvantages of that, i remember some post about it saying its hard to make work, anyone here skilled with doing that i could just like, pay actually lol. would be cheaper than the 5500$ chimera, i dont need its 5000w something around 750-1200w would be plenty
 
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eh friction motor but kinda interesting "The entire thing weighs less than 1 kg plus the battery @ 626 grams."
Friction drives are hopelessly inefficient. The ones that drive the tire tread can throw away half their juice that way. Even the ones that drive the rim are very sad compared to mechanical or direct drive.
 
😆 Some aftermarket kit promos. (Hey people are paying 2500$ for new titanium rear triangle to shoehorn in a crappy 250w Internal battery hub)

Idk about the Ti brompton strength but the main one is HARDY but made of hi tensile steel, I've seen clones on alibaba of chromo or alu for400, could get some made with disc brake support which also normally requires expensive mods and 20 wheels which is also crazy expensive in uk
 

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I demoed this official one and it was absolute crap, 250w, unwieldy front carrier block mount battery, FWD, broke down on me , it does that a lot apparently

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Brompton cultists are up there with Apple diehards... the 5500 dollar titanium brompton doesn't even have disc brakes, which you're probably gonna want on ebike like the one they cobbled together... a lot of these mods replace so much it hardly seems like anything original is there

 

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The Chimera is too much at 5kw, 750 to 1500w would be ideal. But it seems to run good at 1kw.

If overheating with this is such a big deal, maybe the statorade and heat fins or just I dunno stap on some liquid nitrogen chamber lol
 
Just curious to see if you are getting any closer to formulating a build plan? Or is that not your objective? 110 posts here at last count.
 
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No doubt I might have missed one, but so far I've only seen one RC motor setup that worked and that was Thud's race bike that used a 2 speed transmission in order to match the RC's motor strengths. It only had to survive a few laps too (which Thud's failed to do).

I would be very worried about heat as they don't have much thermomass. Maybe with water cooling like the big RC boats use. Not a lot of air goes past at bicycle speeds either.
 
No doubt I might have missed one, but so far I've only seen one RC motor setup that worked
Are you forgetting (our old friend now passed), Ozzie Jesters self built cruiser with the big Turnigy 80100 ?
..or those slick and almost invisible friction drives from Keppler ?
 
No doubt I might have missed one, but so far I've only seen one RC motor setup that worked and that was Thud's race bike that used a 2 speed transmission in order to match the RC's motor strengths. It only had to survive a few laps too (which Thud's failed to do).

I would be very worried about heat as they don't have much thermomass. Maybe with water cooling like the big RC boats use. Not a lot of air goes past at bicycle speeds either.
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any idea on what this is, with the transmission and all. says he messed around with astro motors and yachiting motors, but decided on a motor thats only ip54, although the transmission is ip67. The bafangs seem more waterproof, driving thru swamps and all lol. but a yachting motor could be sweet. Whole system is only 7lb but also requires a special rear hub. I thought about buying this bike actually but its like 5,500$ and might not support schwalbe MPlus 24x1.75 with the custom hubs and all, runs 24x3, guy never really replied to me or w/e

As far as a brompton goes, are there any ultra narrow 750w+ rear hub motors that would fit within a narrow triangle or even modified
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theres a couple of rear 250w systems, the former requires a whole new rear triangle, this boost one is like 36v 250w and maybe has a proprietary BS battery and isnt out yet so no torture testing. 2,500$ and 600$

putting a good 750w+ into the rear wheel without having all that hub wheel weight would be so fun

maybe some alibaba chaps could make a scaled down clone system and hubs to fit different bikes, i guess the chimera system as-is requires a custom frame space mount but im sure that could be worked around with a smaller motor and transmission. the chimera is like 1000w minimum 3800w max and has pretty terrible range. but it does do backflips!


Are you forgetting (our old friend now passed), Ozzie Jesters self built cruiser with the big Turnigy 80100 ?
got a link?

the brompton seems like the safest option for gettin' rad but i've tried their 250w front hub motor and it's ass , literally broke down on me as it has with tons of people. maybe the GRIN saw20 500w is better. They said it only does 52v but i think theres an adapter that lets you run it with their 72v controller up to 800-900w. But front motors are goofy, Sadly the Saw20 has no rear hub option, although they said maybe a mount on it could be adapted to run rear hub. Not sure if it would even fit the standard triangle.

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i guess some adapters exist or DIY is possible Converting a front hub motor to a rear?
i just shot an email to Crystalyte too
 
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HOSS

Curious what the rear clearance max for Brompton is, front fork is 74mm ish for hub. Even some small 500w rc type motor rigged up to the back would be better than this, but worst case scenario rigging up a narrow 500-1000w hub rear would be neat . I think this has proprietary batteries and all that junk, waiting to see what they say. Those poor Europeans and their 250w 15mph laws ..

I guess brompton dropout space is 112mm? Here's a 250w 110 https://www.aliexpress.us/item/2251832824149176.html?gatewayAdapt=glo2usa4itemAdapt


This 1500w supposedly fits 110m dropout but I wonder if after relacing, it would fit 16" Brompton specific rims BMX 26 inch 48V 52V 1500W rear hub motor wheel
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It's hard to say whether those little high psi brompton wheels will take a rear hub motor plus your weight though
 
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Are you forgetting (our old friend now passed), Ozzie Jesters self built cruiser with the big Turnigy 80100 ?
..or those slick and almost invisible friction drives from Keppler ?
I don't know how I forgot about AJ. Interesting man who was ahead of his time. I have nothing but respect for anybody who accomplished what he did while stuck in a wheelchair.

Be sure to watch the video of him in the link above.
 
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Anyone have experience with the LEAFBIKE 500/1000/1500w rear hub motors? They're only 110m wide which should fit brompton. 16 inch 48V 52V 1000W electric bike kit - rear hub motor wheel I don't think this one quite fits brompton tire however, might have to lace a motor up
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Well, that 16+ pound motor would go in a Brompton the same way that a Cummins diesel would go in a Miata. Which is to say, you can do that, but it would negate the best things about both parts.
 
Well, that 16+ pound motor would go in a Brompton the same way that a Cummins diesel would go in a Miata. Which is to say, you can do that, but it would negate the best things about both parts.
ye they have an 8lb 500w +lace/rim one too, maybe that would be adequate eh. Still dont think it fits brompton wheels with its stock rims (Rim Fit For: 16 × 1.5" / 1.75" / 1.95" tire) vs 16x1.35 . Maybe. This one is geared actually which is interesting. And swapping the goofy super heavy rear shifting hub on a brompton for something like this would make sense at least.

They have a narrow 1500w one too, maybe some other stuff also. I think they sell just the unlaced motors and maybe some other narrow stuff. BMX 26 inch 48V 52V 1500W rear hub motor wheel

looks like just the 1000w motor is like 13lb.


Disadvantages of a geared hub?

looks like the geared 500w with controller is about 11lb laced with rim. Not sure if they sell it unlaced 16 inch 48V 52V 500W rear brushless geared hub motor - electric bike kit
 
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