Deraileur 28.6 mm clamp -need something nicer

[Smiley]

Anybody know of a sexier clamp for my new Bedford, seems like somebody would make a nicer piece for 28.6 mm tube clamp.

http://aebike.com/page.cfm?pageid=30&action=details&sku=DP6221

[gman]

Campy makes a very nice black one, as does SRAM as well. They are much more "finished" looking than the generic looking Shimano.

[Dave Wages]

Well, since the "Carbon Conspiracy" has set in, there ain't no good 28.6 clamp-on front derailleurs any more. What I found is a simple little plastic shim that fits inside a 31.8 front derailleur. If you didn't know it was there you'd never notice it. I get them from QBP, but if you can't find one, let me know, I'll get you the hook up! ;)

[David Kirk]

The Parlee carbon adapter is the ****.

Dave

[cadence90]

Dave(s),
On a 28.6 seat tube, doesn't a 31.8 clamp adapter with a shim move the front derailleur out over the crankset incorrectly? Or is it not enough distance (1.6mm) to make a difference?

[eric007]

Dave -- you're supposed to be on vacation, go back to looking at condors and elk.

But the Parlee carbon derailleur clamp comes in 28.6 and is lovely.

[woolly]

Dave(s),
On a 28.6 seat tube, doesn't a 31.8 clamp adapter with a shim move the front derailleur out over the crankset incorrectly? Or is it not enough distance (1.6mm) to make a difference?

Think "concentric circles" - the shim is just taking up the space equally on all sides of the circle in between the derailleur clamp & seat tube. The Derailleur doesn't know whether it's on a 31.8 seat tube or a 28.6 with spacer.

[thwart]

I've used the 28.6 shim and it works well; the 31 mm FD just stands out a bit above the seat tube rather than directly on it. Very subtle.

Did find it a little fidgety to set up (and keep it square and hidden) when installing the FD; probably should have used some adhesive to hold it to the FD clamp.

But that Parlee clamp sure looks ni-i-ice... :p

And dirt cheap. :D

[cadence90]

Think "concentric circles" - the shim is just taking up the space equally on all sides of the circle in between the derailleur clamp & seat tube. The Derailleur doesn't know whether it's on a 31.8 seat tube or a 28.6 with spacer.
I do understand geometry, thanks.

A crankset installed on a 28.6mm seat tube frame is located at "x" mm from the seat tube.
A front derailleur installed on a 28.6mm clamp on a 28.6mm seat tube is located in the correct plane, horizontally, relative to said crankset.
31.8mm - 28.6mm = 3.2mm / 2 (that "concentricity thing") = 1.6mm.
Therefore, a derailleur installed on a 31.8mm adapter with shim on a 28.6 seat tube is located 1.6mm outboard of the same derailleur installed on a 28.6mm clamp.
The derailleur, in fact, (especially if it's a really smart one like a Campa) knows that it is 1.6mm away from "home".

Hence my question.

I have no idea what you mean by "a 31.8 seat tube or a 28.6 with spacer."
I'm talking, as is everyone else here imho, about a 31.8mm clamp adapter with a spacer, on a 28.6mm seat tube, versus a 28.6mm clamp on a 28.6mm seat tube.

[Ti Designs]

Let's see if I have this right: You feel the front derailleur clamps that adapt an 1-1/8" tube to a braze-on shifter are below the quality of the bike - OK, I can see that. Thing is, there are no moving parts to a front derailleur clamp, this is a question of who wants to sculpt a piece to do the job. I have a milling machine and a good supply of aluminum, a fair amount of titanium, I love milling prototypes in Delrin, or I could use stainless lugs to match the lug work on the frame and do some creative silver brazing to add on a derailleur tab. It might wind up costing $800, but I'm sure I'm up to the task...

[David Kirk]

Let's see if I have this right: You feel the front derailleur clamps that adapt an 1-1/8" tube to a braze-on shifter are below the quality of the bike - OK, I can see that. Thing is, there are no moving parts to a front derailleur clamp, this is a question of who wants to sculpt a piece to do the job. I have a milling machine and a good supply of aluminum, a fair amount of titanium, I love milling prototypes in Delrin, or I could use stainless lugs to match the lug work on the frame and do some creative silver brazing to add on a derailleur tab. It might wind up costing $800, but I'm sure I'm up to the task...

I just mailed a blank check to you. Start making chips.

Dave

[Ti Designs]

I just mailed a blank check to you. Start making chips.

Very odd projects are taking over my machine shop. Right now I'm working on custom knobs for a stereo with machined flutes which expose the purple heart wood under the metal. Then I have a piano keyboard knife handle in the works using wenge for the black keys and maple for the white ones with paper thin slices of black walnut between them. Once those are done I'm sure I can make a shifter clamp that's up to your standards - will heart shaped cut-outs be OK, or do I need to go two tone blue with a reverse curve?

[Brian Smith]

I just mailed a blank check to you. Start making chips.

Dave

If the $800 tag didn't give you pause, send one here, too.
The derailer will be in the spot a 31.8 clamp puts it.
The second through twentieth clamp get cheaper.

You could sell them to Smiley and recoup your investment, over time naturally...

[MarcusPless]

Anybody know of a sexier clamp for my new Bedford, seems like somebody would make a nicer piece for 28.6 mm tube clamp.

http://aebike.com/page.cfm?pageid=30&action=details&sku=DP6221


I seem to recall that e-Ritchie bought a bunch of these from Campy when they were discontinued. You might email him to see if he has any left.

--Marcus

[RudAwkning]

I seem to recall that e-Ritchie bought a bunch of these from Campy when they were discontinued. You might email him to see if he has any left.

--Marcus

I think e-Richie bought the clamps for Campy FDs. They used to be interchangable by simply unscrewing the allen bolt. You could convert a Bz-on to a 28.6/31.8/35 and vice versa. The newer high end models (Chorus and Record QS era) featured rivets instead of the allen bolt which I believe can't be removed.

I've pillaged many 28.6 clamps from old Centaur and Racing T FDs and put them on my Record FDs.

[Ken Robb]

I think the silver adapter in the photo Smiley posted looks good. What am I missing? I know: good taste. :rolleyes:

[DHallerman]

Why not just search around online for a good 28.6mm clamp front derailleur?

Recently I've found both a Campy Record and a Campy Centaur, both 10-speed, both with 28.6mm clamps (pre-QS though).

I found these on Total Cycling (UK, but US-ship), Texas Cyclesport (some good deals there), and could likely find on eBay, too

What kind of chainrings and drivetrain are you setting up?

Dave, who has enough steel bikes to want those smaller FDs

[MarcusPless]

I think e-Richie bought the clamps for Campy FDs. They used to be interchangable by simply unscrewing the allen bolt. You could convert a Bz-on to a 28.6/31.8/35 and vice versa. The newer high end models (Chorus and Record QS era) featured rivets instead of the allen bolt which I believe can't be removed.

I've pillaged many 28.6 clamps from old Centaur and Racing T FDs and put them on my Record FDs.


Ahhh, didn't know about the newer derailleurs. All of mine are shiny Chorus. Despite their advanced age they still seem to work. :D

[Jeff N.]

I have a brand new Campy Mirage fron derailleur with fixed 28.6 clamp. Shiney Silver. 25 bucks shipped. Problem solved! Jeff N.

[Lifelover]

I'm having a different problem that I now have the answer too.

I have a new frame that is measuring 29.7 where the derailler goes. My 28.6 is super tight and after fiddling just a few minutes I was not able to get it on.

I guess I just need to get a 31.8 and used 1/2 the shim.