XACD made titanium tandem bike frame we designed with 6pcs coupler, the frame head tube we designed with 44mm bigger head tube, sand blast Logo on the down tube. 10" disc barke. Also we designed and produce the matched front fork. If you like this titanium tandem bike frame pls let we know, good price and best quality will be belong you. Remember all the detail specifications can detail size can be customize according to your side.