dogman dan
1 PW
Another Idea I've been stewing on for some time. A home brew extracycle type attachment. Bolt it to any frame, with one part of it customized for use with a particular frame. The main part of it though, should fit most bikes.
MINIMAL WELDING INVOLVED. So if this works, a good first project for the novice.
The basic Idea here is to get another affordable, compact longtail bike. So the goal is not a bike 2 feet longer, but a bike 8 or 9 inches longer. The advantages are a shorter parking length, a lighter bike, and short enough to carry on a rear bike rack on a car. But still having the better ride that results from a longer space between the seat tube and the rear wheel.
The idea is to start out with a swing arm from a used up, cheap ass MTB. You see these bikes new for less than $150, and the absolute max I'll pay for a used one is $50. Junk ones, 10-20 bucks at yard sales. In the USA at least, these bikes are at every garage sale if you get there early.
Also possible, and I'll try this too, is do the same idea with the ass half of a bmx bike.
Along the way, a disc brake mount will be added to the attachment.
Heres the parts bike. One of my first commuters, I pretty much wore out this bike after 2000 miles. One bit of historical interest, it was the first e bike to race the gas bikes in the Death Race in Tucson.

Remove this part of it. The entire black swing arm is mild steel. Pretty easy for even novice welders to work with.

The approximate attachment points. It will bolt to the drop outs, and a bar will bolt to the shock mount. The other end of the bar will be custom length, so it can attach with some kind of large clamp on mount, to the seat tube. It might include a second bar, that bolts to the seat tube lower at the bb, or higher, at the seat stays. Bolt to a caliper brake mount or something like that perhaps?

So a tab gets welded to the arm at the black arrow.
Pipe bolts to the arm at the shock mount at the yellow arrow. The tube will have to be the exact right size to fit good. It could be welded there if bolt on fails to be stiff enough.
At the blue arrow, the other end of the tube would have a fairly long, split in half tube welded on. That would allow some kind of clamp type attach to the seat tube. Possibly even just 4-6 hose clamps.

The tricky part, will be whether this can be done, without creating a rubbing chain on a bolt or something. Nice if you don't need to add a pulley to re position the chain.
This will end up as a 26" wheel attachment. But once finished, I'll explore whether it can be used with a 20" wheel.
MINIMAL WELDING INVOLVED. So if this works, a good first project for the novice.
The basic Idea here is to get another affordable, compact longtail bike. So the goal is not a bike 2 feet longer, but a bike 8 or 9 inches longer. The advantages are a shorter parking length, a lighter bike, and short enough to carry on a rear bike rack on a car. But still having the better ride that results from a longer space between the seat tube and the rear wheel.
The idea is to start out with a swing arm from a used up, cheap ass MTB. You see these bikes new for less than $150, and the absolute max I'll pay for a used one is $50. Junk ones, 10-20 bucks at yard sales. In the USA at least, these bikes are at every garage sale if you get there early.
Also possible, and I'll try this too, is do the same idea with the ass half of a bmx bike.
Along the way, a disc brake mount will be added to the attachment.
Heres the parts bike. One of my first commuters, I pretty much wore out this bike after 2000 miles. One bit of historical interest, it was the first e bike to race the gas bikes in the Death Race in Tucson.

Remove this part of it. The entire black swing arm is mild steel. Pretty easy for even novice welders to work with.

The approximate attachment points. It will bolt to the drop outs, and a bar will bolt to the shock mount. The other end of the bar will be custom length, so it can attach with some kind of large clamp on mount, to the seat tube. It might include a second bar, that bolts to the seat tube lower at the bb, or higher, at the seat stays. Bolt to a caliper brake mount or something like that perhaps?

So a tab gets welded to the arm at the black arrow.
Pipe bolts to the arm at the shock mount at the yellow arrow. The tube will have to be the exact right size to fit good. It could be welded there if bolt on fails to be stiff enough.
At the blue arrow, the other end of the tube would have a fairly long, split in half tube welded on. That would allow some kind of clamp type attach to the seat tube. Possibly even just 4-6 hose clamps.

The tricky part, will be whether this can be done, without creating a rubbing chain on a bolt or something. Nice if you don't need to add a pulley to re position the chain.
This will end up as a 26" wheel attachment. But once finished, I'll explore whether it can be used with a 20" wheel.