JakcBeNimble

This is a followup to my earlier question thread about my dad's bike boom vintage Torpado. I converted its drivetrain to be 2x7 with an old RSX STI shifter for the rear gear.

I found it earlier this year being ridden for the first time in 20 years when I came home for awhile, but still in sorry mechanical shape. Let me just say this up front: I can't stand friction shifting for rear gears, and I also am not a fan of downtube shifters. Retro considerations aside, modern STI and Ergo shifters are functionally better in every possible way. I found myself with a pile of spare parts and time to kill, so I gathered up a few extra pieces of housing and some cables, and went to work.



Here it is as I found it:




Here's the original 10 speed friction shifting drivetrain:




I had to take off the rear downtube shifter and use the old post to hold the housing stop (lower left corner) for the STI shifter. Originally, the housing stop was too big for the post and the nut wouldn't thread onto the bolt, but some filing of the housing stop got it down to size.





Here's the upgraded drivetrain. It was tough to find a index compatible derailleur that had the claw attachment around the wheel axle.





Here's the cockpit with the new parts. It looks (and feels) a little goofy with the mismatched brake levers, but it works great and it a huge improvement over the original state.





And here's the finished product:





I know this was probably alot of work for such an old and not very high quality frame, but it has huge sentimental value. It also only cost me about $65 total thanks to Recycled Cycles in Seattle and their bins of used parts. It rides great and shifts smooth, except that it will rub slightly in the small/small gear combo. My dad doesn't ride hard or far, so I'm not too worried about long term durability.

One issue I wasn't able to completely solve is that the seat clamp won't keep the seat level, no matter how hard I clamp it and after disassembly/cleaning. If anyone has an idea of how to solve this, let me know.

Thanks for looking, and feel free to ask questions.

joejack951

The seat clamp was probably overtightened at some point or if it's a one bolt post, it's possible that someone mangled the steps on the post or clamp. Given how cheap seatposts are, I'd just replace it with a Kalloy post (~$12) and be done with it.

JakcBeNimble

The serrations on the plates of the seat clamp were almost flattened, so it had definitely been overtightened at some point and I may just have to replace it. Luckily I can probably get one alot cheaper than $12 at Recycled Cycles.

joejack951

If the serrations were flattened it's likely that the bike was used with the clamp loose and the movement of the two serrated pieces against each other wore away the steps. Overtightening the clamp would not wear down the serrations. Regardless, the fix is cheap. I'm curious though, what constitutes "a lot cheaper than $12"? You can't go much lower. Make sure your new (used) post doesn't have the same problem.

Grand Bois

You could have added a claw to any rear derailer.

That seat cheapens the look of the bike.

10 Wheels

Looks Good.

JakcBeNimble

I can probably swing one for $5 at the LBS from their bin of used parts. I'll have to dig through it find one the right size and that's not destroyed already, but I'm sure that I'll find one.



I didn't want to go hunting for the claw attachment because I was doing this on the cheap, and this solution worked out nicely. It cost me about $5 for the RD.

Ironically, that's the OEM seat that came with it long, long ago.