Because mini bikes are cool.

[RogerPapaMike]

Who here has built a mini bike, either from a kit, from scratch, or somewhere in between? I really want to build one for cheap, and was looking for tips, pointers, and pics. I looked online, and just found a bunch of vague wikihows and video. I figured you guys and gals have all the knowledge about tiny two wheeled vehicles ever. Thanks for the help.

[MrAtom]

I made a motorized bike out of a weedeater engine. It's not too dissimilar. If I were gonna make a minibike, I'd get a Briggs rototiller off craigslist and either make the frame from scratch or find a crappy dirtbike and drop the engine out, or build it off of this bike frame (bought one for $30, sold it for $60, ymmv):



There's a lot of possibilities with minibikes. What were you hoping for?

[RogerPapaMike]

that looks really great. where is the motor? i was thinking something along these lines, but a bit less shiny.

[alex.s]

i've built a couple and have many bought fully assembled. are you a fabricator already?

[RogerPapaMike]

Originally Posted by alex.s

i've built a couple and have many bought fully assembled. are you a fabricator already?

the most ive done is cut down fairings and make a licsence plate/tail light bracket out of scrap aluminum.

[alex.s]

you got a welder?

[RogerPapaMike]

Originally Posted by alex.s

you got a welder?

Not that I own, but access to one/buddies with more experience.

[alex.s]

start learning about steel. it's actually very complex. learn what carbon does to iron, read about nickel and also read about and what chromium does. learn what heat does to steel grains. read about annealing and hardening. (specifically how steel becomes stressed and how those stresses affect the strength.) after that, have him teach you how to weld. (mig welding is probably the easiest to learn) then buy a mandrel tube bender (NOT A PIPE BENDER) then start welding things together. once you can make a structure that wont fall apart, build the bike how you like it. you'll probably also want access to a lathe. a mill helps a ton also. presses are very handy as well. a big hammer goes a long way in fabrication.

you will probably make lots of mistakes. make sure you learn from your mistakes.

you probably want to start with soft steel like a1020 or something. its cheap and easy to use and wont cause you many headaches. but knowing about how the steel acts when heated and how different types of cooling changes it is important when welding. it's hard to screw up soft steel, but you'll need that knowledge down the road. especially if you want to do anything with a 3, 4 or 5 series steel... or basically anything that isn't a 1 series.

[RogerPapaMike]

Originally Posted by alex.s

you will probably make lots of mistakes. make sure you learn from your mistakes.

Oh, yeah I'm good at mistakes. Most of my time with a wrench is spent undoing them. I like doing things my way, swearing a bunch and then figuring out the right way.

[JohnnyBravo]

I want one... I get to ride my nieces though

[alex.s]

we have a couple clones of these blata b1's. they wheelie pretty well.

[JohnnyBravo]

^ them things cost almost as much as a Ninjette new

[Sirref]

Originally Posted by JohnnyBravo

^ them things cost almost as much as a Ninjette new

looking at it, that sounds about right

[alex.s]

the chinese clone costs about $300