I've been thinking of this bike design and I want your opinion. Feel free to tell me if this plan is crap and I'd like some ideas on how to make it better.
I'm thinking of a custom built frame, as the title says, a break-apart, minivelo longtail with an integrated rack and front suspension. I wanted a longtail, something like the Surly Big Dummy or the Kona Ute, because of its practicality - but I'm not sure I'd like to own a bike of that length. I think one way of reducing the length of the bike would be to use 20 inch tires, and make the rear chainstays not too long. Xtracycle extends the wheelbase about 15 inches but I think I'll be happy with an extra 8 to 10 inches of extended wheelbase. If an xtracycle bike would have 30+ inches of chainstay length, my plan would be to go 22 to 25 inches - this brings the BB to the center of the wheelbase.
I also want front suspension, and plan to use standard (26") MTB suspension forks with 20" wheels, and use disk brakes.
My initial plan is to use the Be-Bike Haze frame as a template, at least for the front of the bike:
Keep the geometry for the front of the bike intact, build an extended rear with an integrated rack, and find a way to break apart the front triangle for easy transport. Standard bike parts keeb the build costs down.
Here's an illustrated guide to what I want to do:
The "ghost" of the be-bike is there so that you can see where the changes were made. The red frame is the front of the bike with be-bike geometry, while the blue rear part shows the extended longtail with the integrated rack.
This shows the bike broken apart. The fork rests on top of the looong seatstays, while the rest of the front triangle falls to one side of the stays. The rear rack can be built wide to accomodate the front triangle. The front wheel is strapped to the side. Skate wheels are shown attached to the rear rack like a brompton.
This shows the bike top side down, so that it can be rolled around. A soft cover can be made, open at the bottom, with straps connected to the rear triangle. When padded with cardboard or newpaper, it should be a large alternative to a suitcase, since the rear rack protects most of the components anyway.
There are a couple of concerns. A bashguard should be sufficient to protect the chainwheel during travel. Disk brakes will give good stopping power, but the rotors might get bent during transport.
The size of the folded package is approx. 40" X 25" x 8" - Narrow but long. Not really it's airline recommended baggage size, but it could go through without excess baggage fees, maybe.
The budget is also a concern. Since there's a definite small budget to making the custom frame, I don't think I can go with S&S couplers for the breakaway angle. I'm thinking the ritchey/dahon system might be easier to replicate, or maybe copy some other coupler that uses bolts instead.