Crank Motor Kit from 8Fun/Bafang BBS01

[cheez&onion]

Hi guys,

I was looking to upgrade my Dahon folder to a electric bike but soon realised with the width of my front wheel, it wouldn't fit.

There is however an oddball that I had found searching the internet, it is suppose to be mounted into a standard bottom bracket and the crank can freewheel while the motor drive the gears in the rear.

Anyone has experience playing with this kit? It is more expensive, see link below...

Aliexpress.com : Buy 36v 250w 8fun central BB motor kit (BBS01) from Reliable central motor kit suppliers on MW motor

 

[trex]

I have one of the BBS01 - run it on 26" wheels, don't know if it's good on smaller wheels.
It's easy to fit and to derestrict. Good thread about it here:
http://www.pedelecs.co.uk/forum/electric-bicycles/14590-8fun-crank-drive-kit.html

 

[Deleted member 4366]

Why not fit a rear motor to your Dahon? The standard chainwheel on the 8Fun crank-drive kit will be too small for normal pedalling.

 

[trex]

I agree with d8veh that rear hub drive is neat on the dahon but the BBS01 is simpler to fit because it does not really need brake switches.

 

[Deleted member 4366]

The standard Dahon chain-wheels are 52T. The crank drive has 46T as far as I can count from the photos, so that's about 11% reduction, not too bad, but the standard gearing works quite well with electric assist. Maybe Bafang do different chain-wheels for different sized wheels.

The hidden wire type brake switches, alleviate all the problems we used to get with brake switches unless you've got hydraulic brakes. You need brake switches anyway with that cranl-drive kit because it runs on a bit when you stop pedalling.

 

[cheez&onion]

Hi,

Sounds like you are pleased with it, any problems with freewheeling the crank? Noise or friction?

 

[cheez&onion]

Yeah it is 52T with 8 speed cassette, I've compared the mechanical drawings, my crank is actually the exact same size at 210mm, is it probably not too bad, I'll be glad if it does 20mph.

 

[trex]

Hi,

Sounds like you are pleased with it, any problems with freewheeling the crank? Noise or friction?

Yes, have it for a month now and I like it. Noise is about the same as my previous 8-Fun rear hub motor but much quieter than the hub motor at high speed. Friction in the motor freewheel is not more than at the rear freewheel, same little ratchet noise. Shemoz may want to confirm this, smooth power delivery and the motor cuts out very quickly as soon as one stops pedalling like on the Bosch motor.

 

[Cyclezee]

Hi cheez&onion,

You could save a lot of bother by just getting one of these, eZee Dahon - electric bikes and conversion kits



Of course I quite understand that if you are happy with your existing Dahon and want a project, converting it can be fun.