This is my website: rjmelendez.blogspot.com check here for some more wacky projects.
Thanks to Abraham Garza, Charles Guan, Victor Rodriguez for their contributions.
Step 1: Get your rolling frame!
Razor Pocket Bikes form the majority of pocket bikes Chiquicycle is a Razor MX350 i got from some people that had taken it apart and were about to throw it away. If you look hard enough you should be able find a couple of used razors for a small cost (<50$).
Honda Minimoto is another popular model.
Also there is a lot of pocket bikes that used to be gas and you can easily convert to electric. These frames tend to be heavier but more sturdy and their brakes are much much better that child motorcycles.
After you get your frame, take a good look at it and try to find any missing parts. Sometimes you won't have the chain, or the driving sprocket. Luckily you should be able to find most of these materials in the internet here are some good resources for pocket bike specific parts!
Many times you can probably replace the original parts by bicycle parts (Chiquicycle has a bicycle handlebar + bicycle seat). In addition the brake levers/cables can definitely be bicycle parts.
We have a "pocket bike gallery" in cambridge MA, we have all sorts of bikes we can convert so don't limit yourself to a specific brand or style!
Make sure your rolling frame (wheels, handlebars, chassis and brakes) are in good condition before you start modifying it.