Mini chopper Trike

[Drummining1monkey]

So for school I have a transportation class where I have to rebuild a small engine and a metals class. I would like to use the motor I rebuild to put on a mini Chopper trike that I want to build in my metals class.
Though I havent really seen anybody who made a non reverse mini trike, I saw some bigger units but nothing to the small scale. Is there any reason that it doesnt seem like anyone has done one? Any pointers or design ideas anyone has to make the process any easier for my first time trying to build one of these?

thanks
-Matt

 

[mike75925]

mini bike/doodlebug with a live-axle. by far the easiest way to make a trike is to take a bike and add an axle that is long enough for 2 wheels.

 

[porsche930dude]

its pretty straight forward. basically build a chopper minibike but with a kart rear axle . Heres a trike i built. Sort of what your going for i guess
http://www.oldminibikes.com/forum/project-logs/1050-my-trike-complete-tons-pics.html

 

[mike75925]

nice collection, especially the mini me and micro me.

 

[Drummining1monkey]

By live axle you mean one with a differential? I don't have one of them and trying not too spend too much money. I know If I used a solid axle I would probable have issues with turns and the wheels wanting to spin different speeds. Would it work alright If I basically just made one drive wheel on the rear axle and had the other one free spin?
That trike is what im kinda going for but more of a chopper feel to it. Yours helps me see how I need to set up the rear then just work it into a chopper frame.

 

[porsche930dude]

no mine is a differential but i made it so it doesnt move. It needs to be so both wheels are powered solid together. It does make it a little harder to turn but thats how it needs to be. If you lift a wheel which a trike often does then it needs the power there or it will lurch when you set back down and youll flip back. Also because it is easy to shift your weight it makes it easier for the inside wheel to slip around corners so turning is less of a problem

 

[Drummining1monkey]

okay that makes things easier not needing the differential. What size/thickness tubing is usually the best building the frame?
Would anyone have an estimate of about how many feet of tubing it would take? I know it all depends on the design and everything just trying to figure a rough cost estimate right now.
I'm basically trying to make it as small as I could to fit a 5hp 4stroke motor on. the motor is in my classroom and forgot to take measurements of it but should be able to tomorrow to see how big the frame would need to be.

 

[mike75925]

for the standard doodle bug frame, figure about 7' per side, 14 total. you need a piece of tubing pipe for your neck, 14". spreader bars, depends on how wide you want her to be. the widest point around 12". so 2@12", maybe a 6 and an 8 depending on placement. spreader bars should be the same size as the main frame tubing. front end, figure 8', 4 for each leg and handle bar. on a side note, they do sell the fork assembly and frame for less than $100. live axle is posi (positive traction), the wheels turn at the same rate. differential is the one where the wheels turn at different rates.