Vintage Motorized Bicycle Plans

Discussion in 'General Questions' started by levsmith, Oct 15, 2008.

  1. levsmith

    levsmith Member

    So i have a machining metals class right now and i just finished a hammer that we are supposed to make and the teacher said that we have to come up with the next project. So i was searching around trying to find some ideas and
    somehow i got to these vintage motorized bicycle plans. I thought it was pretty interesting even though it doesn't have pedals.

    i didn't really find much to make though. so if anyone has any ideas of something to make out of metal on a lathe, (preferably for a bicycle but anything will work now) i would really appreciate it. thanks

  2. oilee

    oilee New Member

    how bout a jack shaft system
  3. CalgarysFool

    CalgarysFool Member

    The gas tanks on these bikes are pretty much all the same, and somewhat ugly.

    Maybe you could fabricate a nice tank that flows with the lines of whatever bike frame you choose.

    There are also plans, somewhere around here, for a springer front fork you can make, too, using springs for a screen door or something.

    This could be a great project. A combination of a found object (bicycle), a few ordered parts (engine kit, sprocket, throttle assembly etc), and some metal shop fabrication (tank, forks, whatever else you can think of...).

    Good luck, and keep us posted.

  4. levsmith

    levsmith Member

    well i dont think i will be able to make the bike because i only have about 6 or 7 class periods left which is only about 24 hours of work time. thanks for the idea about the springer front forks. i may do that for the chopper but i think i will make a springer seat post first. any recommendations on what kind of spring to use for the seat post? thanks.
  5. sparky

    sparky Active Member

    My suggestion is work more time after class official hours... and get 'er done. So you can...

  6. levsmith

    levsmith Member

    hey thanks for the reply but i really wasn't planning on building the bike. I could build it at home easier than at school since we have a welder and I know where all the tools are. I'll try to make it a little more clear. I have to make something on a lathe, since that is what we learned how to use in the class. I think i will make a springer seat post for the chopper since it doesn't have any suspension. That is if i can find some plans for one. Sorry if i wasn't clear enough the first time.
  7. jvirginillo

    jvirginillo New Member

    Carb adapter?

    I know very little about using a lathe or any other metalwork power tools for that matter. I have been playing around with the idea of adapting a better carb to the china bike motor and thought building an adapter would be agood project. ??
  8. levsmith

    levsmith Member

    hmm sounds interesting. what kind of carb? what does your idea of the adapter look like.
  9. jvirginillo

    jvirginillo New Member

    Carb adapter

    So the idea is 'stolen' from the old aircooled VW's. There is an adapter plate that solves the problem when the 'adapted'

    Here is a link

    the new carb would attach to the adapter using the bolts and nuts (must be countersunk on the side attaching to the block. then the adapter is bolted to the block.

    Problem is you 'lose' the intake runner.

    The whole design on thes motors for the carb to manifold needs a rework.

    A nice little Mikuni or knockoff would be nicer bolted to an aftermarket manifold. Now there is a project that I am sure is 'doable'

    Wouldn't a piece of pipe with flanges welded to it do the job for our intake manifold?

    As long as the runner is the same length and diameter I can't imagine it wouldn't work but maybe I am over simplifying things.

    My son is getting me a Loncin carb off of a 70 CC kids ATV. I am going to try adapting it.
  10. levsmith

    levsmith Member

    if the piece would look like that, then it would be done on a mill, not a lathe, but thanks for the idea though.
  11. Gungatim

    Gungatim Member

    you could make a simple chain tensioner, that is a common weak point. Probably only take an hour or two to turn a nice aluminum version and press in a bearing, maybe make a stronger clamping system with a 30deg. adjusting arm instead of the vertical adjustment.
  12. Gungatim

    Gungatim Member

    Or how about a nice aluminum throttle to replace the cheap plastic one. Knurl the center and polish the ends...another 2 hour project in shop.