Chain Drive How To's?

[HankMontgomery]

Hello everyone,

I am new to this forum and this is my first post.
I have just started my first E Bike build and of coarse that comes with a long learning process. I have one specific question though; how to get the motor to drive the back wheel.
I have a single speed cruiser that I want to convert and i have most of the parts (motor, controller, throttle, odds and ends). my original plan was to get a flip flop fixie hub and driive the fixed gear side with the motor and the freewheel side with the pedals, somehow make sure it does not unscrew itself. The problem is; I would rather the motor not spin when I pedal or coast. Sadly dual freewheel hubs do not exist to my knowledge (with exception to the BMX flip flop hubs, though i do not think those would work unless there are freewheel sprockets that thread on backwards?)
So lately i have been looking at chain drive systems, you know, chaining the motor straight to the crank system. it seems like with the right kind of dual freewheel sprocket chainwheel, it should work. But i am confused.
Bikes mechanics are new to me, and my bike nut friends are not used to strapping motors to their rigs.
Ant help or tips OR LINKS TO RELEVANT FORUMS, would be nice. And very appreciated.

[amberwolf]

There are many many chain drive systems here on ES; I would recommend looking thru the various build threads for "mid drive", "chain drive", "bottom bracket drive" (bb), "stoke monkey" (sm), "cyclone", etc. The search function in the forum can help you find some of these; others you may want to use the Site Search function in Google to locate.

If you look thru the CrazyBike2 link in my signature you'll also find some recycled-parts ways of doing it.

There are lots of possibilities, depending on your DIY skill level or desire, vs finding kits to do it.


Pictures and specifications of what you already have, as well as exactly what performance you expect out of it, and what loads you need to pull/carry over exactly what kind of terrain, would help others be able to suggest more specific options.

[Lebowski]

you can build your own motor using a bicycle rear-axle. This gets you easy attachement
of chain drive and freewheel all in one. I did it and it works great.

[Miles]

Sadly dual freewheel hubs do not exist to my knowledge (with exception to the BMX flip flop hubs, though i do not think those would work unless there are freewheel sprockets that thread on backwards?)

Flip flop hubs are no good - they have RH threads on both sides. Bi-drive/Dual-drive BMX hubs were made for a while - these have LH threads on the LH side. The DK Dual-drive could even accommodate either standard 1 3/8" or 30mm freewheels.

EV deals sell the Currie hub: http://www.evdeals.com/USPD%20Drive%20Parts.htm (scroll down to "Currie USPD rear wheel hub").

http://www.bikeparts.com/productinfo/AC ... 52095.html

viewtopic.php?f=28&t=12449

viewtopic.php?f=28&t=13532

http://endless-sphere.com/forums/viewto ... 28&t=17602

viewtopic.php?f=28&t=37640

[Tench]

Freewheels are available with a left hand thread, you may need to use one of these on your motor to prevent it from screwing itself off the motor under load if you are going to drive the chain wheel on the right side of a bicycle. This would also allow you to pedal and or coast without the motor being driven round. Any good machine shop could machine a left hand thread onto your motor or make an adaptor to enable you to mount a left hand thread (southpaw) freewheel. Cylone motors get around the need for a left hand thread by mounting the freewheel from behind so it screws outwards against a shoulder on the adaptor which is splined onto the motor shaft.

Left hand freewheel;
http://www.ebay.co.uk/itm/BMX-FREEWHEEL ... 5d2c06a72b

Cyclone drive adaptor;
http://eclipsebikes.com/tooth-cyclone-d ... -1001.html

Freewheel cranks are also available frome there, these allow the motor to drive through them to the wheel without the pedals going round;
http://eclipsebikes.com/freewheel-chain ... 2_119.html

Both of my builds in the links below use a motor driving through the cranks in this way, the first with the cyclone system and the second with a left hand thread machined on the motor.

Simon.

[Grinhill]

With your original plan, there is a way to use a standard right-hand-threaded freewheel for a left-hand-side drive system. Simply have the freewheel on the front sprocket (attached to motor), then have a fixed sprocket on the left hand side of the rear wheel. If your wheel has the 6-bolt ISO mounts for a brake disc, these can be used to mount a sprocket carrier (adapter).

The chain and sprockets will still spin whenever the wheel turns, however it will not have to push your motor around.

Is this the sort of thing you were describing?

[HankMontgomery]

Yes Grinhill that's what my original plan was all about. But because the bike is single speed i don't have a lot of room back there and i would like to install disk breaks. so that's where the chain drive system idea came into play. I was eyeing the eclips chain-wheel, i like the idea of a freewheel motor sprocket with the freewheel bike chainwheel. also what is the difference between the 1 and 3 chainwheel?

Also thank you everyone for your replys. Every forum has its own personality and it very refreshing to stumble upon one with a kind one.

Hank

[HankMontgomery]

Also, i looked more into the cyclone kits and they supply the parts for their chainwheel assemblies here:
http://www.cyclone-tw.com/order-chainwheel.htm
I have also heard about some problems with the truness of these systems
Im in america so it might be easier to get one of these kits vs the eclips part. Are these things even the same thing?

Hank

[Miles]

Hank,

You might want to take a look at this thread:
viewtopic.php?f=28&t=25153

[torqueon]

Try these guys out, they sell hubs that have both a left handed thread and right handed thread, and have left handed threaded free wheels, all compatible.

The site is http://www.staton-inc.com/

Happy motoring !!

[HankMontgomery]

Eclipsebikes will not ship to the US. kinda a problem.
Hank