Fixing a dropout - too closed, or too open
 

Since we deal with vintage, steel frames in our hobby/addiction, sometimes we run into problems that are easily fixable, if only we knew how. Here I show how I use an 8" adjustable wrench to open or close the hanger.

First, use a caliper to measure the opening from front to rear. On Campy compatible dropouts it should be 10mm.

If it's narrow at the opening, you need to open it up. Just stick the wrench in and tweak. Start with very low force and work your way up, measuring in between.https://cimg0.ibsrv.net/gimg/bikefor...feeace217e.jpg

That's pretty easy, obviously you can use other tools to do this.

But what if the dropout is too "open"? Measure the same way, if it's more than 10mm at the opening, you can close it up with that same 8" adjutable wrench.

Every 8" adjustable wrench I've ever seen has a "hole" at the end of the lever arm so you can hang the wrench on a pegboard. Hook that on the derailleur hanger stop, and you can use the wrench as a lever.https://cimg9.ibsrv.net/gimg/bikefor...581aa76f5c.jpg

You've got a ton of leverage, be gentle on your tweak.

https://cimg7.ibsrv.net/gimg/bikefor...ec9877fa08.jpg

Are there other tools that do the same thing? I'm sure there are, but an 8" adjustable wrench is about as common a tool as one can find. Oddly, I've found that a 6" or 10" wrench "hole" isn't quite the right size.

Nice technique! And a readily-available tool. Thanks.
My tool for dropouts that have been squeezed shut is the business end of a large cold chisel used as a wedge and slowly tapped into the slot.
Brent

https://cimg8.ibsrv.net/gimg/bikefor...f6e343564a.jpg
Its all about leverage. :)

https://cimg0.ibsrv.net/gimg/bikefor...82d91c26fa.jpg

Archimedes would be proud.

Huh. Now I'm trying to remember how I did it when I had a too-wide-open dropout the last time I sent a derailleur into the spokes.

Probably involved a large rock and loud cusswords. :mad:

I think you should have used a bigger hammer:

https://farm5.staticflickr.com/4890/...e7d69cc2_b.jpg

The BFH, ultimate in precision. :thumb:

Exactly! :thumb:

I would be inclined to grind a notch in the wrench to get it in the crook of the notch of the hanger for a better bite with less chance of rounding the stop, just my 2c. ;)

Been doing it this way for years, never had an issue with it.

Remember to check the edge of the threaded hole for the dropout adjuster screws. Cracks love to start at that thin edge from the stress.

Better technique: get someone to braze in vertical dropouts.

Not surprised, when you've got it, you've got it. :thumb:

I tend to err on the side of caution for myself, measure 2 or 3 times, cut once, etc, etc.

Naw, measure once, cut twice, buy more material.

You end up with more scrap for future projects that way.

:innocent:

Yeah, I end up with a lot of scrap anyway.