I decided to design my own mini bike. I made this to challenge my 3D modeling skills and also make something that is really cool. I am going to be sharing some of my design details that could be used to design a larger bike.
The dimensions need to be relevant to the size of wheels you are using and your height . You can always scale the model after you are done. My design was meant for a small makerbot. The picture attached to this sketch will give you an idea. Make your dimension proportional to this.