The first step was to find a design I liked, which I did after stumbling upon the MadAss scooter from germany. I was looking for a headlight and this popped up.
Now I liked the fact that the gas tank was integrated in the main frame tube and the under tail exhaust. I mean, that is some hot shit.

Then it was off to find a fork. After talking to Yam I decided to go with a CR80 dirt bike front end. I mean, come on, it's gotta be unique if I'm building it. So I picked up an entire front end for $157.24 shipped. I even won the frame so I had the guy cut the steer tube off so I didn't have to make a new one and could just weld it to the front of my frame.
Now onto the powerplant. As I said, it's an 80cc scooter from 1984. What is going to be rocking about this setup is the rear wheel is a 10" while the front wheel is a 17". Oh yes!
Check out that manly 1" exhaust port. Screaming I tell ya!
All the other bits I've kept for this day.
Now, I could have gone with round tube like the MadAss scooter, but I wanted to make like a little easier since I don't have a tube notcher and settled on 2x4 rectangle tube.
I needed to make some handlebars because I didn't want to buy any. Remember, the goal is $400. I must use whatever methods I have to keep me under that. So I had some 7/8" stock lying around and after some cuts, welds, and sanding it turned into this.
From here it got real boring. It came down to cleaning everything so this baby looks pretty new when I try and sell it once it's done for about a grand. My logic is that the new MadAss sells for $2K with a 49cc motor. Granted mine is a bit older but with how clean it will be and the bigger motor I'm hoping for $1K.
Oh that's right....check out that sweet single sided swinger! MMMMM, TASTEY!
Then I got backed up in the paint booth so I just had taped off parts lying around. Damn that guy in the paint booth taking his sweet time...

And a few of the painted parts.
Welp that's it for progress thus far. Ideas and comments are always welcome. Free parts are good too.

I will keep a tally of costs to see if I stay under budget. I'm not counting consumables that I already have lying around like welding wire, paint, sand paper, etc. Only things that I had to go and buy specifically for this build.
Frame Material = $15
Front end = $157.24
Rectifier = $30
Low Fuel Sender = $11.99
POR-15 Tank Liner = $21.45
Exhaust Metal = $11.39
Oil line nipple = $3.00
EBC Brake Shoes = $12.55
Gold Fren Brake Pads = $14.35
Grips = $6.87
Air Valve Cap = $3.58
Shipping = $4
Total = $288.42
Man Hours Invested (MHI) = ~17
This going to be a tight one. I know for a fact I still need new front and rear brake pads, grips, a front tire (can't really ride the knobbies on the road real well), tank liner, header and muffler(will be homemade but need materials) and a headlight. I'm really hoping I get a deal on the powdercoating. It's going to be close folks! Stay tuned!