New Front Deraileurs for Half-step (+ granny)

[GAJett]

I have ridden with a half-step+granny almost exclusively since about 1976 (thanks Frank Berto).  I absolutely love these setups.  My two current rides have only a 3-tooth difference up front (49-46-26 and 44-41-24).  These are a converted 1974 Raleigh Competition and a 2010 A. Homer Hilson.  Successful and reliable shifting has been done with a Suntour Superbe, a Suntour Cyclone, and a Huret Jubilee  All worked without any problems, even the delicate Jubilee.  I suspect that most older racing derailleurs would also work (e.g., Campagnolo, Shimano, Zeus, etc).

Is anyone aware of any modern derailleurs that can shift over such narrow 3 to 5-tooth difference ranges?  Mountain bike derailleurs have the necessary throw but the deep inner cages interfere with the middle ring while trying to shift to the outer -- so those are out.  Descriptions of almost all the "racing" derailleurs are described as having a throw that is limited only to double cranksets -- so those seem to be out as well.

So what are my options?

a.  Advice about specific "racing" styles that are known to work over a triple;

b.  Many current "racing" styles really CAN shift over a triple -- go for it;
c.  Many current "racing" styles really can be easily modified to do so (like filing down stops);
d.  Stay old school and order vintage parts.

I've searched a dozen or more conversations here and have not found any clear answers.  I'm sure many of you can steer me right (and that any decisions based on your inputs are on my own head and everyone else is blameless for their guidance).

Thanks all for your wisdom,

GAJett

[Patrick Moore]

Where do you find rings in the 40-50 teeth range in odd teeth numbers?

--
You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bun...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/rbw-owners-bunch/5c5f7595-13e5-4668-8053-d7756a6b37dcn%40googlegroups.com.

--

Patrick Moore

Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum

-------------------------------------------------------------------------------------------------------

Executive resumes, LinkedIn profiles, bios, letters, and other writing services

-------------------------------------------------------------------------------------------------------

When thou didst not, savage, know thine own meaning,

But wouldst gabble like a thing most brutish,

I endowed thy purposes with words that made them known.

[Garth]

Probably a Microshift double R8 or R9 should work . Don't go by any specs mfrs. give, they are but mfr. intended/recommended parameters they assume the average buyer would use. Every road double FD since the beginning of time will say something like a 16t capacity for 52/53t max ring. Those aren't limitations. I ran a 1999 105 5500 series double FD with a 26/44/48 and 26/36/50 without a hiccup. That's part of the fun of DIY, seeing what works and what doesn't, off the beaten path. Undocumented, not-supposed-to work, and all that jazz :)

[GAJett]

See my contribution to the recent "Preparing Bleriot to Sell--Seeking Advice" conversation.  Peter White (https://www.peterwhitecycles.com/tach.php) currently lists TA making odd-toothed chainrings for 110 bcd cranks and some others.  Here is the abbreviated list:

GENERAL CHAINRINGS FOR COMPACT CRANKSETS
110mm Syrius 11 Speed Chainrings for Compact Cranksets
Description
TA Syrius 11 110mm 39 teeth black
TA Syrius 11 110mm 53 teeth black

110mm Zephyr Chainrings for Compact Double Cranksets and Triples
Description
TA Zephyr 110mm inner 33 teeth black
TA Zephyr 110mm inner 33 teeth silver
TA Zephyr 110mm middle 39 teeth black
TA Zephyr 110mm middle 39 teeth silver
TA Zephyr 110mm outer 45 teeth black
TA Zephyr 110mm outer 49 teeth black
TA Zephyr 110mm outer 49 teeth silver
TA Zephyr 110mm outer 51 teeth black
TA Zephyr 110mm outer 51 teeth silver
TA Zephyr 110mm outer 53 teeth black

TA Zephyr 110mm outer 53 teeth silver

So they are out there but getting harder and harder to find.  That's part of why likely go to a 4-tooth difference on my next build.

GAJett

[GAJett]

Thanks Garth.  I have one bookmarked for future reference.
GAJett

[Bill Lindsay]

In my opinion there is no new production front derailleur for half-step.  The key objective feature that a half-step front derailleur needs in order to be considered a half-step front der is an inner cage that does not reach far below the outer cage.  Everything that is current is designed for a 14 or a 16 tooth jump, so the inner cage reaches WAY below the outer cage.  That's something that is straightforward to look at, and nothing contemporary is going to have that.  If one wants to run a new production front derailleur with a half-step setup, then they will just need to run the derailleur a lot higher above the big ring than is considered normal or optimal.  There are lots of people who say "I run my FD an inch above the rings and it still shifts fine". The fact is the job of a front derailleur is pretty darn simple, particularly in friction set ups.  

For me, when I'm doing a half-step build, I always use a vintage Shimano derailleur that was designed for half-step.  Tons were made, and they rarely wear out, and nobody wants them today, so they are cheap on eBay.  Just type half-step front into the eBay search bar and there are many to choose from.  Just as a test, I put 5 or 6 of them on my watch list and I've already been given discount offers on a few of them.  

Bill Lindsay

El Cerrito, CA