OK, new plan. Somethng like the last bit above.
26" front (bent rim fusin) and 24" rear (old broken wheel off CB2), Trek 26" frame, Specialized 29" shock fork, 24" rear triangle, skateboard platform as seat, Skareb shock fork as rear spring, cruiser bars in seattube, 9C/GM hub in frame.
Naturally, lots of the above stuff doesn't fit together right, but it gives the idea of what I am after. For one, the brake studs are in an unusable position on the 29" fork, relative to a 26" rim:
and if I use a hubmotor up there I can't use a disc brake. Actually, the allloy fork has no provision for disc anyway.
There's a slight possibility I could go crazy with it, and flip the brake arms upside down...then have them be *pushed together* from the outside, rather than pulled together from the inside, but I'm not sure I can devise something reliable to do that. If I could, then I can use the 26" front in this 29" wheel and still use it's rim brakes.
Since it's a 24" rear triangle, a 26" rear wheel won't fit in it properly. If I remove the caliper brakes currently on it, the wheel might fit with sufficient clearance below the brake mounting bar. But the studs on it are for 24", so unless I do something to "extend" the brake arms, the pads won't reach the rim from side-pull or other stud-mounted brakes.
However, since the triangle is steel, I *could* weld a disc-caliper mount on it. I have no rear hub that will take a disc, *but* I do have a front and a rear hub (both of which have one threaded side) from Karma that are identical in core diameter, and could be cut and welded together to make a rear hub that I can then use one of several thread-on disc adapters I have, along with one of the discs I have in sizes from 140mm to 180mm.
Now, that brings up another possibility--a wide wheel. I could take those two hubs, place them unthreaded end to unthreaded end, and weld them together just outside the bearing cups, with bearings pre-trapped inside (just not yet greased). Weld two axles together end to end so I'd have one long enough to reach thru the whole thing. Then lace them up to two separate rims, but cross-lacing them so that the spokes from each hub's "inner" flange go to the holes to the opposite rim, but the outer spoke flanges are laced to the rim on that hub. This might not work out, so might have to just lace them as two individual rims.
Anyway, if it were laced up to two rims on one extended dual hub, the wheel would be stronger *and* it would have two tires and two tubes to take the cargo load, and keep my worry load for a flat down. I haven't had them with the slime liners and slime, but if it does happen on the cargo bike with it loaded down, I'd have to unload it all to fix it.
But really, it's just to spread the load between two rims and twice as many spokes, and give me more rear traction, too, because....
I'd like to run this with a middrive based on a 9C/GM motor from Icecube57, as a first test (eventually would like to go high enough voltage to run that treadmill motor properly):
There is *just* enough space with this thing sitting down low in the middle triangle and offset as far as possible to one side to get a sprocket and chain onto it. It'd be bolted via spacers directly to the side cover, as this was a front 9C case, and I have yet to find anyone with 9C rear covers they'd part with.
I also considered a belt drive, running directly on the hub's ring between the spoke flanges, but I doubt that I'd be lucky enough for that circumference to line up with any of the belts I already have, for a full circle of belt teeth. A chain drive would be stronger anyway, for the kind of loads I'm looking at pulling, probably, given the belts I have are used or older.
All I would have to do is weld up some dropouts to the stays, to bolt the motor to. Probably out of 1/4" plate steel, with clamping-style horizontal dropouts to negate the need for torque arms.
Then the chain would go to probably a jackshaft that combines the pedals and motor via freewheels, and runs back to the regular bike drivetrain.
I would probably weld on a pivot point plate for the rear shock triangle, so taht I can use the actual dropouts of the Trek frame for the jackshaft (which might end up being the one from CrazyBIke2 that Thud is making, depending on how successful this bike design works out to be).
I'd need to also make a plate for the shock fork to mount to on the Trek frame, and on the rear shock triangle, so that it can pivot at the ends to allow swivel and shock action.
I could fit the NiMH packs in here if I needed to:
but I'd rather use the 10 TS cells. More weight but LOTS more power and range.
Bike looks skinny still:
but that's without the cargo pods and stuff that would actually make it useful. I'm still thinking I'll use those folding cots to make fold-out cargo racks along with the fabric computer carriers that can also fold up, to make a bike that isn't as bulky looking as CrazyBIke2, and can fit in more places when not loaded up. It should also be shorter than CB2, by a little.
Unfortunately it won't be a no-weld bolt-together bike this way; there's just too many little things I can't reliably make without welding them on.
But it will still be semi-recumbent. That skateboard on top of the back end can be the seat. Not quite like you see there, but I can probably heat-bend the laminated board into a comfy shape for a seat. Then bolt it to rails I'll be bolting or welding from the Trek's front part of the downtube, across the seattube sides, and the seat stays, cantilevered out over the top of the shock triangle. Supports for these rails at the rear will be triangulated from the rear end of the rails down to the dropout area of the Trek frame, and X-ed across too, right in front of the max forward position of the seatpost of the shock triangle, for lateral stiffness.
The seat will bolt to those rails, and the cargo pods will hang from them too. So it has to be stiff. They will probably be 1.25" or 1.5" square tubing, whichever I have enough of.
The rear triangle would be cut about halfway down it's seatpost, and the seat stays moved down to that point, so that it will be much lower and not possibly be an issue with hitting the bottom of the seat or rails.
If there is too much bounciness with the shock fork as rear suspension, I have some long pneumatic assists for a rear cargo hatch off a car. They're not sufficient to be suspension, but they have a lot of drag in either direction pushing or pulling, and will help dampen the suspension. If I don't have to use them for that, I'm going to use the rose/heim joints at one end of each to make my steering tie rod, which runs from the handlebars in the Trek seattube up to the actual steering stem in the front fork.
I might not use the seat tube itself to hold the bars, but may weld on an old headset to the trek top tube via a bracket, to put the steering farther forward, dependng on how my leg position works out.
Sound crazy enough yet?
I'm considering using both motors; the little fusin for most riding, and the middrive 9C/GM for power riding or cargo hauling.
Maybe this bike minus all the cargo stuff will become the Death Race 2011 bike.