Modifying a front derailleur from braze-on to clamp style

[RPS]

I have a Shimano Ultegra triple front derailleur with 1-1/8 clamp that is damaged. My son located and bought a replacement but he could only find it in braze-on style (was told the 1-1/8 clamps were next to impossible to get), so I bought a 1-1/4 Shimano clamp and clamp spacers. The problem is a clamp won’t work.

In looking at the derailleurs they look identical but for the clamp versus braze-on mounting (and the old one being bent :rolleyes: ). Anyway, it looks like I should be able to take apart the new braze-on derailleur linkages and reassemble on the old clamp mount (the mount itself looks fine). Since I usually thrown away Shimano equipment when worn I have never taken a FD apart to find out how much force the return spring is under. I plan to back out the travel adjustment screw to relieve as much pressure as possible before taking anything apart but there is the risk than once taken apart I may find it very hard to reassemble.

Looks easy but is there more to it than what appears on the surface? Have any of you taken one apart and then reassembled?

Thanks in advance

[Mike748]

I haven't done this with a Shimano FD but I have with a Campy. As long as the mounting bosses that the two screws go into are spaced the same you shouldn't have any problems. The spring is self contained and should be ok. Loosen the stop screw all the way, remove the two fastening screws (one for campy), and slide the two linkages off the mount. Off the bike is much easier.

[John M]

I think that it would be much easier to use the braze-on with a 1 1/8" adapter clamp. There are some available that look pretty nice.

[Ken Robb]

I think that it would be much easier to use the braze-on with a 1 1/8" adapter clamp. There are some available that look pretty nice.

I have a nice one made by IRD and I know they are not the only manufacturer.

[RPS]

I haven't done this with a Shimano FD but I have with a Campy. As long as the mounting bosses that the two screws go into are spaced the same you shouldn't have any problems. The spring is self contained and should be ok. Loosen the stop screw all the way, remove the two fastening screws (one for campy), and slide the two linkages off the mount. Off the bike is much easier.
Thanks Mike. By backing the inner travel screw all the way first the derailleur's parallelogram bottomed out onto itself, so when I removed the two screws the spring was kept from further unloading -- which is what I was concerned about.

Was very easy and only took a minute or two -- actually took me longer to clean the old clamp once apart than to make the change.

[RPS]

I think that it would be much easier to use the braze-on with a 1 1/8" adapter clamp. There are some available that look pretty nice.
That was my plan until I discovered the Shimano clamp added height which I don't have.

[Mike748]

Good deal, glad it worked out.

[AndrewS]

That was my plan until I discovered the Shimano clamp added height which I don't have.
Just curious: Added height in what way? Is there a bottle braze on in the way?

I use adapters with all my bikes and haven't run into a problem, so I'm curious how a clamp works when an adapter won't, especially with a not so thick 1 1/8" seat tube.

I'd be shocked if anything Shimano came apart. They like their rivets.