Finding a Custom Sprocket for an Electric Motor Bike

[hobbles]

I have an electric motor that I want to use with a bike chain and not the small chain that is already on it. Using cad and getting a custom sprocket made might be the way to go, but finding a site that sells them would be more than likely be cheaper. I found that it is called a dual-d boreand is 2/16" thick, from inside one half circle to the other half circle is 6/16", the width between the flat sides is 5/16" and from the very edge of one tooth to the other is 1" but I would like it to be 2" on the one I am going to buy. Sorry if I didnt give enough information but I never really work with gears and things because of how little I know about them and usually go with belts but everything is set up for a bike chain so any help would be great.

 

[Trudge]

Hi Hobbles,
I think your best bet is to attach a soft neoprene wheel on the end of the motor shaft.
Something like a skateboard wheel would do. Attach the motor behind the seat post of the bicycle so the neoprene wheel is pressing against the top of the rear tire. (make sure the rotation of the motor will turn the rear tire forward)
Then, by choosing different sizes of neoprene wheels you can find out what is ridable for your weight and style of riding. That is taking into consideration the torque of your motor, your nicad battery. With the above setup you'll have the gear ratio that you'll need if you decide to sink money into a sprocket and chain system. The gear ratio being the neoprene wheel you finally decide on and the outside diameter of the rear bicycle tire.
Also there are battery conserving 'grip' throttle type devices sold for trolling motors (in pawn shops). That might be a good choice later.

 

[Trudge]

Hobbles,
I reread your post and now realize that you might not be talking about building a motorized bicycle. In that case I have a sprocket made for a shaft. Let me give you the specs and the manufacturer.
The hole in the sprocket for the shaft is regular keyed ( like most pulleys).
Requires a motor shaft size diameter of 5/16 inch
Total inside depth of shaft hole is 7/16 inch.
It is a 22 tooth sprocket made for a bicycle chain.
From about where the chain would rest in the sprocket, from top pin of chain to bottom pin of chain, exactly 3 1/2 inches.
This is an electroplated sprocket (color between copper and brown).
It is manufactured by Lida Machinery CO. LTD
It says "Dicta Brand" on it.
Also it has a ratchet type device inside, so the sprocket will only engage one way.
Once there is nothing driving it, it freewheels.
Hope this helps.
Good luck.