clamp-on vs braze-on

rparedes

Are there any advantages/disadvantages of front Derailleur being clamp-on vs
braze-on?

alfeng

Older clamp-on derailleurs often marred the paint on the seat tube ...

Not counting older FRENCH bikes which had slightly smaller seat tubes ... there are at least three different clamp sizes for front derailleurs, so you need the RIGHT SIZE for the particular frame.

If you have the right size clamp-on front derailleur for the particular frame you are working on then the adjustment should be fairly quick & easy ...

Now, FWIW, my impresson from only THREE (Italian) frames (so, the sample may not be meaningful OR it may be an Italian-thing) which have braze-on front derailleur mounts is that more-often-than-not (i.e., on all three, but that could just be coincidence & your observation OR those of others may be different) YOU have to align the braze-on ... something the framemaker should do before sending the frame off to be painted and/or something the LBS should do!

TOO OFTEN you will read about people depending on the imprecision of the slot & bolt to align the derailleur cage ... that is, they never bother to align the braze-on; so, while simply positioning the derailleur at the the proper height & position on an un-aligned braze-on using the anchoring bolt is often a good-enough way to make the adjustment, doing so is actually, IMO, more tedious than tweaking the braze-on (as far as I know, the braze-on is soft steel regardless of whether the frame is steel, aluminum, or carbon fiber ... and probably, Titanium/etc.) into proper alignment whereby you only need to move the derailleur up-or-down to make any adjustments without needing to be troubled with cage orientation ...

If/Once a braze-on is aligned, adjusting the front derailleur is actually easier since you don't have to stand over the bike & view the alignment from above while make the adjustment for the particular chainring size ... of course, some people NEVER change the size of their chainrings, so the convenience of aligning the braze-on may be moot.

rparedes

The reason I asked was to clarify: if at some point I change from a compact double to a standard double does it matter whether it's clamp-on or braze-on?
Thanks for your response.
Happy new year!

alfeng

I've read of SOME instances where the braze-on mount was too high, but I presume that if you were to buy a NEW frame that was made in the last two-or-three years that you would not have any problem using a crank whose outer ring was between 48t-54t ... but, ask the framemaker or distributor about their specific specs.

dosedependent

Braze-on is my choice. It allows for greater flexibility if you have different chain ring sizes that you use. Especially if you want to change between a 53 and a 55.




DoseDependent


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