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Discussion Starter · #1 ·
I have an old 1988 steel Bianchi with a braze-on front derailleur hanger. I just put on a new crank, replacing a 53/47 with a 47/30 set of cogs. For the small ring, the front derailleur sits about 2 or 3 cm too high. Am I doomed, or is there a way to extend this? Unfortunately I don't think there is quite enough room simply to put a clamp below the hanger.
 

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Ain't gonna work.
Back in 1988, only little girls would ride a 47/30....A 50/34, or 36 might work.

You can use a round file to open up the braze on, on the bottom side, a little.
 

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Discussion Starter · #3 ·
Thanks. That's extremely helpful, especially the first part. I'm setting it up for my daughter. I'll let her know.

When I bought the bike in Feb 1988, the gearing was appropriate for climbing Mt. Diablo in CA.
 

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Discussion Starter · #5 ·
Yeah, I think that is the only hope. Just ordered one...
 

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This is the problem with brazed on tabs.

I've never done this, but is it feasible to carefully grind off the offending tab? So a clamp will fit.
 

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SRAM braze-on front derailleurs have TWO mounting holes, vertically aligned. They permit the derailleur to be used with a compact or standard crank and a brazed-on fitting which I guess is mounted a standard distance from the bottom bracket.

Outfitting the bike with SRAM may be an option.
 

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Discussion Starter · #8 ·
I'm going to try the cheap and easy fix first. I'd like to keep as many of the original campy parts as possible. Also, this is my second frame. I broke the first one within a year or so. It cracked at the FD braze-on, which makes me worry about it being a point of weakness and makes me not want to mess with it. I would rather just put the original crank back on.
 

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I use a shimano clamp... at it's widest point it's not even 2cm.. so hopefully it can fit.
 

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I'm thinking you could take a Dremel and grind away some metal on the lower part of the slot of the braze-on.

If that doesn't work, I'm guessing a compact 50/34 would work with the braze-on as is. Might you be able to exchange the new crank? If you really need more hill climbing prowess than a 34 ring can give you, you could probably upgrade the cassette.
 

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Discussion Starter · #11 ·
Well Ive ordered the adapter and hpoefully it will solve the problem without having to get more drastic. Meanwhile, thanks everyone for the suggestions.
 

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Discussion Starter · #12 ·
Unfortunately I don't think there is quite enough room simply to put a clamp below the hanger.
Confirmed. Fsck me.

I started grinding on it with a dremmel. This will take about 5 years and weaken the attachment, but at least I don't have to grind the frame braze-on.
 

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Did you consider changing out the front derailleur with one designed for a triple crankset? They are designed for 30 tooth chain rings and smaller. I have never used one on a double before but it might work. I hate triples by the way.

I am a 61 year old big guy and ride a 46-34 crank on my Bianchi Infinito with a 12-28 on the back. So I guess Hans and Frans would call me a "girly mon". If you ride fast enough nobody notices.
 

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Discussion Starter · #14 ·
Yeah, I will probably have to do something like that. I wanted to keep the original Crampy. I shimmed it with a washer and it is working reasonably well now, tilted back a wee bit.

Anyone need a partially dremmeled adapter?
 
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