Converting a little folder

[Peter.Bridge]

I wanted a bike that I could do a bit of exploring when we go on holiday in our campervan. My wife has a lovely little folder that I have got my eyes on





I had a little ride on it just now and it put a big smile on my face !

Roughly 75mm between front forks

I was wondering about a front hub kit :

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Just use the recommended controller

@Woosh do you do a similar kit ?

 

[Woosh]

I might have what you need. Will check for you Monday.

 

[Peter.Bridge]

Thanks 20" wheel 406 rim

 

[Woosh]

we have front, rear (in 135mm drop out) and middle motors for your little folder.
I have asked Andy to get in touch.

 

[Peter.Bridge]

Thanks, spoke to Andy, the front fork spacing is 75mm which is too narrow for the Woosh options

I could do a rear wheel conversion, but I would have to change from the original 6 speed free wheel to a cassette.

I'm leaning towards doing using the topbikekit akm74 front wheel conversion kit and using a Woosh battery bag for ease of conversion.

Just tried a 10 mile ride before I did the conversion with 500ft of elevation gain - it was great, very comfortable, I managed to average 13 mph according to Fitbit, and to pedal some (flattish) miles at 15.5 mph average speed - the gearing really was the limiting factor, but I guess there is nothing I can do about that - freewheel minimum teeth is 14t ? (So 52t*14t *20 inch wheels) It's only a campervan bike so I can live it as is.

 

[Woosh]

freewheel minimum teeth is 14t ? (So 52t*14t *20 inch wheels) It's only a campervan bike so I can live it as is.

For front wheel option, I have the motor with 75mm dropout but not in 406 rim. You would have to lace the wheel. That's why Andy suggests the DWG2NC kit.
14T to 11T gives about 21% more gear inches. I thought that for folders, the cost of upgrading freewheel to cassette is justified when you ride on electrics. BTW, I think we have some 20" with freewheel bafang kits in our store rooom. We used them on our Gale folding bikes.

 

[saneagle]

Thanks, spoke to Andy, the front fork spacing is 75mm which is too narrow for the Woosh options

I could do a rear wheel conversion, but I would have to change from the original 6 speed free wheel to a cassette.

I'm leaning towards doing using the topbikekit akm74 front wheel conversion kit and using a Woosh battery bag for ease of conversion.

Just tried a 10 mile ride before I did the conversion with 500ft of elevation gain - it was great, very comfortable, I managed to average 13 mph according to Fitbit, and to pedal some (flattish) miles at 15.5 mph average speed - the gearing really was the limiting factor, but I guess there is nothing I can do about that - freewheel minimum teeth is 14t ? (So 52t*14t *20 inch wheels) It's only a campervan bike so I can live it as is.

You can buy freewheels that have 11T on the top gear. They're 7-speed, but should work OK with 6-speed shifters leaving off bottom gear, or you can get 7 speed derailleur and shifter for next to nothing.

https://www.amazon.co.uk/DRIFT-MANIAC-Speed-Freewheel-11-32/dp/B07XYNSHZC/ref=sr_1_1?crid=337JOMLD9J59A&dib=eyJ2IjoiMSJ9.SyhruTNnqu5TJIOzMr38z11UWllcslrQ2NDgLTXArkXl-dTTkoSnnoP6z3uyNT8_-wi7aN_QtoycwAgS0BFoxUNDjGJC-fx_WRAQ-Ntsj83zr_0U0u_2RXj3rBj_l5OaY6sRE1qKCPGHjHbYJZwQjdrpJIUnRn2ryH0AloTRkC-7q5MAnhKjAM7nTNFduYEhd4_2C2A9F0WAcMMkrkU1SAU7Cj_KN8dvpREFAhewgLaiD_1_IrZV0-9Ygh0nY_dUORoGCYxL44-fe8ha2qpTZTf5j1N9C9HsSJpQRBdwQSc._b4bKs_666sDLYTUsMll8TG_H3T2Q-rt4x7zVOUwoGo&dib_tag=se&keywords=dnp%2Bfreewheel%2B11-30&qid=1717428504&sprefix=dnp%2Bfreewheel%2B11-30%2Caps%2C87&sr=8-1&th=1

You might find that a cassette motor is too wide for your drop-outs and/or the rim will end up badly offset from the centre of the bike, so be careful. What is your actual width between rear drop-outs?

 

[Peter.Bridge]

You can buy freewheels that have 11T on the top gear. They're 7-speed, but should work OK with 6-speed shifters leaving off bottom gear, or you can get 7 speed derailleur and shifter for next to nothing.

https://www.amazon.co.uk/DRIFT-MANIAC-Speed-Freewheel-11-32/dp/B07XYNSHZC/ref=sr_1_1?crid=337JOMLD9J59A&dib=eyJ2IjoiMSJ9.SyhruTNnqu5TJIOzMr38z11UWllcslrQ2NDgLTXArkXl-dTTkoSnnoP6z3uyNT8_-wi7aN_QtoycwAgS0BFoxUNDjGJC-fx_WRAQ-Ntsj83zr_0U0u_2RXj3rBj_l5OaY6sRE1qKCPGHjHbYJZwQjdrpJIUnRn2ryH0AloTRkC-7q5MAnhKjAM7nTNFduYEhd4_2C2A9F0WAcMMkrkU1SAU7Cj_KN8dvpREFAhewgLaiD_1_IrZV0-9Ygh0nY_dUORoGCYxL44-fe8ha2qpTZTf5j1N9C9HsSJpQRBdwQSc._b4bKs_666sDLYTUsMll8TG_H3T2Q-rt4x7zVOUwoGo&dib_tag=se&keywords=dnp%2Bfreewheel%2B11-30&qid=1717428504&sprefix=dnp%2Bfreewheel%2B11-30%2Caps%2C87&sr=8-1&th=1

You might find that a cassette motor is too wide for your drop-outs and/or the rim will end up badly offset from the centre of the bike, so be careful. What is your actual width between rear drop-outs?

135mm

I'm thinking of using the AKM-74 front hub wheel kit from topbikekit https://www.aliexpress.com/item/1005005986142926.html

and the Woosh 36v 10Ah bag battery


Ends up with quite a light conversion

But I would definitely consider changing to the 7 speed freewheel with 11t for higher top end speed as a separate project - I might leave it as 6 speed and not use the biggest cog - possibly don't need it with the motor assist (eta ordered it - thanks @saneagle )

 

[Peter.Bridge]

Ok - before conversion !





I might try the same circuit with @saneagle 's 11-28 freewheel (can I average 14 mph ? !) and then again after I've converted it with the microhub (1.5kg akm75) and Woosh bag battery (1.8kg)

 

[saneagle]

Ok - before conversion !

View attachment 58006
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I might try the same circuit with @saneagle 's 11-28 freewheel (can I average 14 mph ? !) and then again after I've converted it with the microhub (1.5kg akm75) and Woosh bag battery (1.8kg)

What are you going to do for brakes?

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[harrys]

I think a light folder, ridden at 12-14 mph, will stop well enough with v-brakes. Anyway, we've accumulated over 10K miles on our 20" folders with v-brakes.

I did change the rear brakes on mine to hydraulic calipers and they are far better, but I did require an adapter, The front would have required a new wheel and fork, Not worth it for my riding speeds,

 

[Peter.Bridge]

Yes, I'm not allowed any more e-bikes but I was allowed to convert my wife's folder otherwise I would have started off with a bike with disc brakes. This is purely a campervan bike to use on our holidays. I was rather surprised how fast it is unpowered, I had assumed it would be massively slower than a full size bike.

I bought that freewheel that @saneagle suggested and it is a lot less frenetic peddling in top gear. (11t vs14t)

Made a bit of difference unpowered and felt less frenetic but I think it will make a bigger difference once the kit is fitted

ETA - you really notice the hills unassisted !

 

[guerney]

I think a light folder, ridden at 12-14 mph, will stop well enough with v-brakes. Anyway, we've accumulated over 10K miles on our 20" folders with v-brakes.

When the wheels are true and the v-brakes well adjusted, they stop my 22.41kg 20" wheeled folding bike conversion well enough. But...

I did change the rear brakes on mine to hydraulic calipers and they are far better, but I did require an adapter

...I'm very curious about what adapter you used, and where you got it from. Also how you installed it. I'd prefer disc brakes to save my rims, because the right ones are increasingly difficult to source.

 

[harrys]

These were designed for gasoline conversions. What I did with them was to remove a lot of metal so it would fit between the dropout and motor, and cut a slot to match the dropout, and position it in a way that I could use existing holes in the frame to hold it. A torque arm like strut was also added.

BBR Tuning Billet Aluminum Disc Brake Caliper Bracket

This works with motorized or standard bicycles and allows you to install a disk brake if you don't have the necessary mounts. No more rim or coaster brakes.

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[harrys]

This type was less metal cutting work. It clamps to the dropout, is designed to push against the frame during braking, and requires a thru-axle or skewer. Position it so a screw can be added thru the dropout to hold it. Cut the plate to match the dropout to allow a hub motor. Make sure it can resist the brake force,

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[guerney]

I was rather surprised how fast it is unpowered, I had assumed it would be massively slower than a full size bike.

20" wheelers can be made speedy, but then you risk your bike featuring a sudden highly undesirable permanent fold or break while you're riding it... and that's something I'm congnisant of, every time I ride my aluminium framed folding bike conversion. I'll find the perfect 20" wheeled steel framed folder someday.

 

[guerney]

This type was less metal cutting work. It clamps to the dropout, is designed to push against the frame during braking, and requires a thru-axle or skewer. Position it so a screw can be added thru the dropout to hold it. Cut the plate to match the dropout to allow a hub motor. Make sure it can resist the brake force,

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Thank you, I'll see if I can use that to install a rear disc brake to my Dahon Helios, which doesn't appear to be compatible with the first adapter.

At that price, it's worth trying to save wearing away the rear rim. I've got a rear cable disc brake from a bike I found dumped in the woods, to test it with. Of course I'll need a new hub etc.

The second adapter is mentioned briefly in this video:

 

[harrys]

RJ the bikeguy taught me a lot about wrenching bikes, but he did need to do further work with that adapter.

Using it with Q100 hub motor. Torque plate over the adapter. To remove wheel, I take off the torque plates on both sides, and the adapter is slotted to allow wheel to come out.

The adapter rests against the frame to resist rotation. There’s a small bracket hose clamped to the chainstay to help keep it there.

 

[harrys]

Same adapter on a 26” frame, regular hub. It’s clamped on in a similar fashion and positioned with a slot so wheel can drop out. It’s clamped to frame with screw on lower left. A second screw resists rotation.

Hydraulic caliper is quite smooth.

 

[Ghost1951]

20" wheelers can be made speedy, but then you risk your bike featuring a sudden highly undesirable permanent fold or break while you're riding it... and that's something I'm congnisant of, every time I ride my aluminium framed folding bike conversion. I'll find the perfect 20" wheeled steel framed folder someday.

That perfect steel framed folder might just be this Pashley Moulton TSR 27 that I used to have and sold about twenty years ago. I rode it powered by me 40 miles in two hours and two minutes. It isn't exactly a folder, but you could withdraw a pin and it came into two pieces so it was easy to fit in the boot of a car. It was a surprisingly fast bike.