Starting an Electric Mini Bike Build

[jsak]

New here, so any help would be appreciated. I recently purchased an old mini bike with the intentions of making it an electric mini bike. I thought that i could just buy some pre-assembled scooter wheels and be done. Alas,the mini bike has a 5/8" axle, so most of the rear wheel scooter assemblies are too small.

So before I even get to the electric motor, batteries, and controller I want to have a rolling chassis. I know that i need a freewheel hub at the rear and I've seen them available at all the usual stores. But I don't really know what wheels they are compatible with. Any ideas?

 

[mckutzy]

I would think the batteries and motor would be first to build around, since they are the biggest pieces.
Secondly what kind of "mini" bike, they range from all sort of sizes.
Whats an example of your Idea

 

[jsak]

Well I have the battery measurements and motor measurements all set. I've used some card board and made cut little boxes to map out where everything will go as well.

This is the type of mini bike that I am talking about.

Actually I have another question. If I can't get a freewheel hub set up, that means when I let off the throttle the chain will continue to spin against an the electric motor. Will that damage the electric motor? Or will the bike slow down because the chain is turning (for lack of a better word) "against" the electric motor? I am really hoping I can find a freewheel hub but I'd like to think that I have another choice.

 

[landuse]

Welcome to the forum. I have no clue about electric stuff, but I would read the sticky on electric motors as a starter. Hopefully someone else can give you a hand

 

[ML-TOYS]

Do you know what motor you will be using ?

 

[jsak]

I will be using a 36volt 1000watt motor that i found at tncscooter
http://tncscooters.com/index.php?route=product/product&path=52_56&product_id=344

I did take a look at the sticky on electric motors and didn't find any info about freewheels or the consequences of not having a freewheel. Thanks for the help, I'm still racking my brain trying to figure this one out.

 

[ML-TOYS]

You may be able to fabricate a jackshaft with the freewheel on that then a sprocket to the wheel.
I will try and look at the freewheels i have at home later to see if i can work it out for you

 

[ML-TOYS]

I also suggest getting a better sprocket for that motor if you can, that chain is like a #25 or basically a 1/4 inch chain.

 

[jsak]

The 8mm chain is a little more heavy duty than a #25 chain which is 6mm. Is it something I can address later? Or do you think it's going to snap right away?

 

[builder bob]

have you considered using a large brushless motor designed for r/c planes? you can get some preaty powerful ones for the about the same price as the motor u posted a link to. depending on what you want the bike to be able to do you also might be able to use some lithium batteries (also designed for planes). if you do some searching you can find a power system close to the same price as a led acid and brushed set up.