I blew some digital dust off of an old submission locked in our WordPress archives and wanted to repost not only because this is a cool hack, but because I would love an update. The original submission came from PB and referenced this site, MPLS MTB, which seems to be out of commission. Hopefully the site did not suffer the same fate as Bike Hacks 1.0.
The DIY longtail/cargo bike PB was working on looked super sweet and PB, if you are still out there we would love an update.
The front half is an old 26er mtb frame that I had been using as an errand/beater bike. The back half is a 29er mtb frame that I had purchased online a couple years ago... it showed up with a bad head tube/down tube weld. When I talked to the shop about getting a new one, they told me to make the frame un-rideable and email them pics. Once they saw that I destroyed the frame, they'd send me a new one.
The two frames are held together at two attachment points: a 127.5mm spindle BB (w/ some washers) in the rear frame is bolted into the rear dropouts of the front frame. Two 3/4" pieces of 6063-T52 aluminum tubing are bolted to the rear frame (through the seat tube and seatpost) and then attach to the front frame (via half an old stem bolted to the front bike's seatpost with a 28.6-27.2 seatpost shim).
If anyone knows PB tell him to give us a shout out.