Bike Design Help Needed

Sounds like fun. There are many things to consider, and I won't cover them all -- partly because I don't have that much time, and partly because this sounds like an educational project, from which you'll benefit only if you do the work yourself.

Bike components are made for loads straight down (perp to axles). You'll need to support both sides of the axles, because the axles are so thin.

Hang out in a Bicycle store for a while and ask questions.

Consider a leaning vehicle (google leaning tricycles, HPV (human powered vehicles), Tony Foale tilting trikes, feet forward motorcycles, Piaggio MP3, four wheel bicycles, quadra(i)cycles). Leaning vehicles are kinder to the components made for bicycles (because the load directions are as intended), and enable the vehicle to be narrrow but still corner well.

Here is a site that links to four wheel "bicycles" that have been built: one is actually two bikes, side-by-side.

http://www.helmets.org/fourwhel.htm#velomobiles

There are few "standard" dimensions for bicycle components: wheels range from 16" to 28" and even wheels and tires for a particular class of bikes (e.g., road racing bikes) vary considerably.

If you google for "performance bicycle" you will find the store by that name, which lists virtually everything you could want for a bicycle. If you spend a couple hours looking around that site you can get a feel for what is available.

As far as overall dimensions, you will want the smallest sizes that carry the intended load, while being large enough to prevent undesirable vehicle dynamics (such as falling over to the side while cornering, or flipping forward during braking). Looking at what has been done will get you into the right ballpark, but you will want to calculate overturning moments, cornering forces, etc. etc. Reading a book or two on vehicle dynamics would be helpful.

Have fun.

Hi Karen, sounds awesome. Check out Freedom Bike Shop on the web or try the Specialized web site. Those guys build the best mountain bikes going and their components are super strong. DeVinci is another great bike also. Hope this helps.

My personal technique @ this point is to procure a specimin of what i want to modify; (eBay is where i often go).

When i have sample in hand, i stare at it a LONG TIME, take it apart, look at it some more! Now i put it back together.

At this point the (old school!) napkin sketching starts.

Hope this helps, it's served me well.

Hi sidevalveguru:

Side valve as in older Harleys and Indians?

Hi Ken, & J.A.P., &al. Current projects include a HotRod with a Lincoln flathead (the V-8) and Junior Dragsters (last bastion of 'free for all' sidevalves).

I love these dinosaurs, because nowhere else is the breathing/thermodynamic balance on quite so keen an edge.