Brazeon FD and Smaller Chainrings?

[David White]

I have recently purchased a 1990's Merckx bicycle and would like to build it up
with a 48x34 chainset. However, the frame includes a brazeon front derailleur
and I understand that these typically do not permit the derailleur to slide
down far enough to accomodate such small chainrings. Short of cutting off the
brazeon and employing a clamp on front derailleur, does anyone have any
suggestions or know of some adapter? Thanks in advance for your help.

 

[A Muzi]

David White wrote:

> I have recently purchased a 1990's Merckx bicycle and would like to
> build it up with a 48x34 chainset. However, the frame includes a brazeon
> front derailleur and I understand that these typically do not permit the
> derailleur to slide down far enough to accomodate such small chainrings.
> Short of cutting off the brazeon and employing a clamp on front
> derailleur, does anyone have any suggestions or know of some adapter?

Just remove it.

No extreme measures, just file it carefully so as not to
remove any metal from the seat tube. Touch up the paint and
use a clamped changer.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

 

[Sheldon Brown]

> white

>> have recently purchased a 1990's Merckx bicycle and would like to
>> build it up with a 48x34 chainset.
>> However, the frame includes a brazeon front derailleur
>> and I understand that these typically do not permit the derailleur to slide
>> down far enough to accomodate such small chainrings.

Peter Chisholms wisely asked:

> Have ya tried it? I have installed a 50/34 and braze-on and it still had room
> to lower it further.

Good point. If you do the math, you'll see that for every 2 teeth off
the big ring, the derailer only needs to move down 1/?" (8 mm.)

However, as I've said before, front derailer braze-ons are the work of
SATAN!

Sheldon "Try Before You Buy" Brown
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[Tom Ace]

Sheldon Brown wrote:

> Good point. If you do the math, you'll see that for every 2 teeth off
> the big ring, the derailer only needs to move down 1/?" (8 mm.)

4mm, not 8mm.


Tom Ace

 

[John Thompson]

On 2004-04-12, Sheldon Brown <[email protected]> wrote:

> However, as I've said before, front derailer braze-ons are the work of
> SATAN!

I knew some guy who insisted on having a braze-on FD mount on his custom
Reynolds 753 frame. Sure enough, a couple months later the seat tube
failed at that point. (Yes, the builder was 753 certified).

--

-John ([email protected])

 

[Paul Kopit]

Frequently a braze on will permit you to get the front derailleur low
enough. Sometimes a little filing at the bottom of the slot works.
OR, get a 50t chainring.

On Mon, 12 Apr 2004 03:04:05 GMT, David White
<[email protected]> wrote:

>I have recently purchased a 1990's Merckx bicycle and would like to build it up
>with a 48x34 chainset. However, the frame includes a brazeon front derailleur
>and I understand that these typically do not permit the derailleur to slide
>down far enough to accomodate such small chainrings. Short of cutting off the
>brazeon and employing a clamp on front derailleur, does anyone have any
>suggestions or know of some adapter? Thanks in advance for your help.