Luke Breen's Separable Monotube Tandem

Luke brought in the tandem he is building for Mary and little Sophie. With 20" (406) rear and 16" (305) front wheels it is very small for a tandem, but very long for a monotube frame. He was able to get a 56mm x 1.1mm 4130 tube from Fairing Industrial Inc., a Tiawanese bike tube manufacturer which has a US office.

This shot shows the joint, made from rings of 1/4" 4130 plate. Might look like overkill, but stresses here will be high. Several 10mm bolts hold the whole thing together, but should allow dissasembly for air travel. Luke, Mary and the girls like to vacation in New Zealand, so this is important.
Also shown is Sophie's beautiful "If you gotta ask, you can't afford it" 135mm Crupi crankset. And, the kickstand mounted to the BB shell.

Nice stuff here. Stays created from "streamline" 4130 tubing, disk brakes, and drilled out mounting tabs for a Rans idler. Also planned is a SRAM 3x9 hub, if the disk brake version ever gets beyond the "vaporware" stage.

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