I'm stumped.
I bought this frame here in Indonesia a few years ago. It came without original paint, but there is some red showing in the head tube and droupout stamping.
The biggest clue, the downtube shifter bosses, was also a bit of a headache to figure out. Notice the orientation of the flat bits: perpendicular to the tube axis. It looks like they are meant to be for Suntour DWL L-1000 levers, although I haven't found a reference to either braze on versions or the dedicated bosses that have been used.
The dropouts and cable guides are referenced in mid 70s Suntour catalogues.
Another clue is the top tube head lug, the pressing is crooked, so the lug point is off centre. Otherwise the workmanship is good.
The frame looks to have been built for 700c wheels. I have had some work done to use 650b wheels and Dia Compe cantilevers.
The seat tube is 51cm c/c with a 52cm TT, c/c.
The seat tube inner diameter at insertion is 26.8mm.
The frame weighs 1930g and the fork 770g.
There is a stamping on the steerer tube, but I've not seen it before.
I assume Japanese origin, owing to the use of Suntour fittings and the fairly light tubing which is seamed (Tange or Ishiwata?). Also, in the mid 70s Indonesian market, quality frames and bikes were often Japanese. I have ruled out Bridgestone, though.
Any thoughts?
I bought this frame here in Indonesia a few years ago. It came without original paint, but there is some red showing in the head tube and droupout stamping.
The biggest clue, the downtube shifter bosses, was also a bit of a headache to figure out. Notice the orientation of the flat bits: perpendicular to the tube axis. It looks like they are meant to be for Suntour DWL L-1000 levers, although I haven't found a reference to either braze on versions or the dedicated bosses that have been used.
The dropouts and cable guides are referenced in mid 70s Suntour catalogues.
Another clue is the top tube head lug, the pressing is crooked, so the lug point is off centre. Otherwise the workmanship is good.
The frame looks to have been built for 700c wheels. I have had some work done to use 650b wheels and Dia Compe cantilevers.
The seat tube is 51cm c/c with a 52cm TT, c/c.
The seat tube inner diameter at insertion is 26.8mm.
The frame weighs 1930g and the fork 770g.
There is a stamping on the steerer tube, but I've not seen it before.
I assume Japanese origin, owing to the use of Suntour fittings and the fairly light tubing which is seamed (Tange or Ishiwata?). Also, in the mid 70s Indonesian market, quality frames and bikes were often Japanese. I have ruled out Bridgestone, though.
Any thoughts?
