Double freewheel motor kits

[Bonzo Banana]

Apologies if there is already a thread about these but just wondered if anyone has any experience of these very cheap kits. I'm not planning to buy one but just curious about them. You have two single speed freewheels attached to the same wheel, one rotated by the cyclist and another by the motor attached to the seat and chain stays via a metal mounting bracket. The kits cost about £60 and obviously doesn't include a charger or battery. It can only be used on a single speed bike or a bike converted to single speed and the rear wheel must be freewheel based. Looks like the motor design has a large speed reducing/torque increasing secondary wheel attached to the sprocket for the chain. In theory looks like quite a simple reliable setup that doesn't cause much drag when the battery is flat? Even comes with a built in front light and horn. I realise it won't be causing the Haibike dealerships any sleepless nights.

 

[sjpt]

I realise it won't be causing the Haibike dealerships any sleepless nights.

I think the sleepless nights will fall on the people who buy this kit.

 

[Bonzo Banana]

Well I can't really defend it as I have no idea of the quality but some of the cheap hub motors available from ebay especially the direct drive models seem very reliable and fit for purpose. This looks like it actually could be quite good and if you used it with a folding bike with small wheels it would get a much easier life however on youtube I think I saw a similar kit fitted to a commercial catering tricycle in India where they seem very popular, I'm guessing such a tricycle would be very low geared anyway but still a lot of weight to move about.

 

[vfr400]

They work as long as your frame has the normal angle at the back. The motors and controllers burn out if you go too slow up hills and they're no longer legal because there's no pedal assist.

 

[Bonzo Banana]

Sounds like its get off and walk up the steep hills then if you don't want to burn out the motor especially as its single speed. As for legality I guess you'd have to go back a few years for that when throttles were legal although I would think adding a pedal sensor wouldn't be too difficult electrically thinking about it and they are about £3 from aliexpress.

Maybe they haven't implemented any sort of cut-out for over-current in the control box.

 

[vfr400]

Sounds like its get off and walk up the steep hills then if you don't want to burn out the motor especially as its single speed. As for legality I guess you'd have to go back a few years for that when throttles were legal although I would think adding a pedal sensor wouldn't be too difficult electrically thinking about it and they are about £3 from aliexpress.

Maybe they haven't implemented any sort of cut-out for over-current in the control box.

It's one thing buying and fitting a pedal sensor, but you need a controller that can deal with it. The one in that kit won't and brushed motor controllers that can are very hard to find.

 

[Bonzo Banana]

It's one thing buying and fitting a pedal sensor, but you need a controller that can deal with it. The one in that kit won't and brushed motor controllers that can are very hard to find.

To be honest as soon as you said brushed motor I lost interest, good spot on that. I would not want a brushed motor on an e-bike. As for the pedal sensor there are videos on youtube showing these motors with a pedal sensor fitted or included. I had thought maybe in the future I might try one on a folding bike I have but a basic quality brushed motor doesn't appeal at all. Still find the kits interesting though. I suspect a brushless version will become available at some point with similar design with an included pedal sensor option. Still amazes me such a kit can be sold for £60 even if it is just a brushed motor.

 

[MikelBikel]

A surprisingly large number of connectors on that controller, if that's the real one and not just a generic pic for the Ad.
If there is just a battery 1, a motor 2, a throttle 3, an on/off switch 4, but also has brake cutouts 5 and light 6.
Good for simple 1 speed bikes.

No need for display 7, Halls 8, PAS 9, Speed 10.. Any more? So many wires & plugs to hide :-(.
I would like a 3 speed auto version that had built in controller, PAS, and a locking switch on the throttle. Just 3 connections.
Cheers, Mikel