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Discussion Starter · #1 · (Edited)
Got a 2nd hand SS over the weekend and thinking of converting it to 1x9 in a month or so depending on how busy I am. I checked all the components and compatibility issues between wheels, cassettes, frames and I'm not sure what to make of this. Below is a picture of the downtube shifter boss. There should be a threaded rod 'thing', right? If there should be one then it must have been from the previous SS conversion (poor frame). Anyway I just wanted to make sure that a 1x9 is possible on this converted frame. I'll be needing a cable stop in place of it.



thanks

CC
 

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This is what remains if you cut and file the boss on the DT. It's difficult and potentially unsafe to go any further with the file!
 

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If by "threaded rod thing" you mean a rod going through the downtube and connecting left and right shifter boss, you should only find one of those on older Cannondale frames. As far as I know, that way of affixing bosses to the downtube was (and may still be) a tightly held Cannondale patent.

If you mean a "rod" that accepts the shifter, it should actually be a stud with a threaded hole.
 

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Discussion Starter · #4 ·
Yes, i was referring to the stud with threaded hole. I just wanted to confirm if it can still be used to mount a cable stop... or anything. I'll probably leave it as a SS now then. I'll grab one of those clamp on cable stops when I convert it back.
 

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Yes, cable stops fit on the same bosses that hold shift levers. Of course, the one in your photo lost its stud. But whole bosses are available from several sources for those who are interested in restoring bikes to their former glory. Article 296 at the link.
http://www.framebuilding.com/Bosses.htm
 

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Discussion Starter · #6 ·
What processes are involved? I've never done much metalwork in my life (so far) but I like tinkering things forever. This seems like an interesting project, but its out of my league. I assume the original has to be grinded off and the new one welded(?) on. Whatabout paint and rust?
thanks guys! I really appreciate it!
 

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clarinetcola said:
What processes are involved?
Generally, these bosses are brazed on, not welded on. Brazing means flowing a melted alloy into a very narrow space between the two parts you want to join, similar to soldering. Heating the area again until the alloy begins to melt will unbond the parts. Brazing burns paint, so I'd wait until just before a repaint before putting a torch to the frame.

Don't really like to recommend that, but since the brazed bond on these bosses isn't very strong, sometimes a forceful yank with a pair of vise-grips or similar will pop the boss or the remains of a boss right off the tube. Not to be tried with thin-walled frame tubing, though...:)
 
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