Shifting issues with TA Pro 5 Vis cranks/rings

[XO-1.org Rough Riders]

Hi:

I've never gotten suitable shifting with a TA Pro 5 Vis crankset with
32/46 rings. This is mated with Shimano 9-speed on the rear (11x34)
and bar-end shifters (Shimano 9 also). First I had it set up with a
Suntour Superbe Pro front derailleur and it wanted to overshift once
every 25 to 50 shifts, no matter how I adjusted the derailleur.

The local bike guru, who knows stuff old and new, suggested a modern
front derailleur, as they are designed to shifter narrower 9/10-speed
chains, whereas the old Suntour derailleur was meant for 6/7-speed
chains. The thought being: Maybe the "old" derailleur's cage is wider
because the chains for which it was intended were wider; now that
wider cage made it throw a narrow chain too far. That make some
sense.

Well, I've installed a brand new Ultegra 10-spd front derailleur and
it seems to keep the chain on either one ring or the other, and it
downshifts fine, but it takes a major tug on the shifter to get it to
move the chain to the big ring. In fact, when I upshift, what it's
trying to do is shove the chain between the rings, into the hole
between the five arms of the right crank, in the sizable vertical gap,
or hole, created by the 14 tooth difference in ring size. Of course,
modern rings, with their ramps and pins, would probably toss that
chain right up onto the big ring instantaneously. But I like the low Q-
factor of these TA arms (this is actually my GF's bike I am talking
about; she's 5'4" and prefer the narrower tread even more than I do),
plus the ring sizes available are preferable to a "compact" design.

Yes, the derailleur is mounted as low as possible abov the top rights.
In fact, the front derailleur cage is so long, it almost hits the
right chainstay down at the bottom. I find that odd since a 46 tooth
big ring is not small, at all. I don't see how this could work on a
crank with a smaller big ring.

Any thoughts or suggestions?

BTW, sorry I don't seem to have a good shot of the bike, or especially
its drivetrain online, though you can see her with the bike (gold 1974
Williams converted to 650B wheels) in front of the Nate Harrison Grade
sign near the bottom of this post:

http://www.xo-1.org/2008/12/rough-riding-northern-san-diego-county.html

We're headed out to Ramona / Black Canyon tomorrow and I'll get some
shots of the parts in question then, in case that might help any of
you help me assay the situation. Here's the blog report of a semi-
similar version of the riding we're doing tomorrow:

http://www.xo-1.org/2009/01/rough-riding-north-eastern-san-diego.html

Thanks.

- Chris Kostman
La Jolla, CA
http://www.adventurecorps.com
http://www.XO-1.org
http://www.the508.com

[James Valiensi]

Chris,
I've been using a TA Pro Vis w/ 33/47 rings and a Campy 9-speed Centaur front derailleur for a long time with no shifting troubles. I could never get a Shimano FD to work with the TA cranksets no matter what gears used.

The Campy 9-speed FD's have a good shape for moving the chain and they are narrow enough to clear the TA Pro Vis arms.

Good Luck!

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James Valiensi, PE
Northridge, CA
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[Gino Zahnd]

I have TA cranks on both my Saluki and Bleriot, and I use the FSA
Gossamer derailer on both. It works smoothly. I highly recommend it.

Bleriot setup is 42x26 for town and the local dirt. Saluki is a
wide-range double: 46x28 for loaded touring. I've also used the FSA/TA
setup with a 48x36, and they all work dandily.

On the Bleriot, I have a Velo Orange 122mm bottom bracket. On the
Saluki, I have a fancy Phil 125 +2 offset.

The derailer cage is pancake flat, which is why it works so well with
the cantankerous TA cranks, and the derailer is specifically designed
for compact cranks, which is perfect for my setups. Here's what it
looks like:
http://bicyclesource.us/images/library/large/fsa_fdgoss_08_m.jpg

P.S. If anyone has a 172.5mm pair, or maybe 170mm, of the "new" TA Pro
5 Vis that they'd like to sell, let me know.

[PATRICK MOORE]

I shifted a 9 sp chain over a 44/30 TA with an old Deore fd using Power Ratchets and had no problems except for the somewhat slow upshift. (In fact, I earlier ran a 26/46 with no problem except a very slow upshift.) I don't recall throwing the chain, but then for the sake of best Q with adequate chainstay clearance, I ran the rings in the middle and granny position and so had more room to adjust the fd optimally -- no need to worry about interference with the crank arm.

Not a solution, necessarily, but at least points to the possibility that there *is* a solution.

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Albuquerque, NM
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[David Faller]

Not to sound pedantic, but this might be a matter of using a FD that is
designed for use with triples vs. doubles. The angle of lift required
for triples is slightly steeper, the arc and length of the FD cage is
larger, and the range of motion is wider. Cage width vis a vis chain
width certainly factors in, but I'd bet using a compatible triple FD
would have a better chance of solving this (emphasis on the elusive term
"compatible"). I don't know from experience, but I've read that Campy
FD's are one of the more forgiving derailleurs.

[MichaelH]

I can confirm this. I have replaced 105 derailleurs with campy CD on
both doubles (48/34) & (44/30) & a triple (48/34/26) and have gotten
significantly improved shifting. The campy feels a little slow on the
tandem(50/36/24) but there is a lot more stress on the chain with a
tandem.

Michael

[James Warren]

I got used to assembling my own bikes and to be economical, I got used to using any old triple FD, usually a Shimano. But when I ordered my AHH from Rivendell a few years ago, I decided to pull out the stops and have Mark assemble it. I needed a FD and trusted Riv's selection, and they went with a Campy triple model called the Champ.

That is the smoothest and fasted shifting front shifter I've ever used. I never was picky about FD performance and can still tolerate slow, laborious shifts, but my experience has definitely been:

Shimano: pretty good, just deal with it
The one time I've used Campy: outstanding

-Jim

[amoll68]

Chris,

I'm running a TA 46-30 on my AHH, and have ended up with an old
Simplex SLJ. This setup does require a bit more shifting finesse than
most modern chain sets, but it's worth it to me. It's been awhile
since I've dropped or thrown a chain - probably due to more precise
technique by the operator. I've got the feel now, but when it's safe,
I'll glance down for a peek while shifting. The last few times I threw
the chain (again, this was awhile ago), I could feel it right away -
stopped pedaling before the chain was all the way off, moved the shift
lever slightly, and back pedaled the chain right back onto the big
ring. Be smooth and relax - finesse.

I have an old Cyclo catalog from the 30s that basically states that
their derailleurs work great - good shifting is up to the technique of
the operator. Then they go on to practically admonish that if you're
not satisfied, you just need to practice more. I think it's a great
little technical article - quite amusing.

Final caveat: I enjoy operating old construction and farm equipment -
I think double clutching is fun, "Brownie" 5+4s are neat, etc.

Here's my setup: http://www.flickr.com/photos/39151498@N07/4377862622/in/set-72157622960184871/

Good luck,
Alex

[stevep33]

I'm using Suntour Superbe Pro FD's with my 46//30 TA's. I've
overshifted small to big a couple of times even though the limit seems
well adjusted on the bike stand. I'd probably opt for a Campy FD
because of the pancake flat shape and performance - is there an online
vender that sells the campy models people like?. Though it's hard to
justify replacing the pretty Suntour FDs because I rarely make FD
shifts, so the overshift is even more rare. I also like that the
Suntour allows pretty good chain line clearance over almost the entire
cassette range for both chainrings.

The FSA Gossamer FD has also worked well for me.

[XO-1.org Rough Riders]

Hi all:

Thanks for your comments and suggestions. Much appreciated!

The derailleur I installed at first yesterday was designed for
triples, and really wants to shove the chain UNDER the big ring when
upshifting (into one of those five gaps). So this morning, just before
the ride, I installed a brand new Dura Ace 10-spd front derailleur
designed for doubles. It has basically flat cage plates on it (as did
the Suntour Superbe Pro this bike used to have). The shifting is OK,
but it takes a lot of trimming to keep it from rubbing on one side or
another as the chain works its way across the cassette.

But the real issue is that now, on some downshifts from the big to
small ring, the chain will ride on top of the small ring's teeth,
instead of engaging the teeth. It's almost like the chain "expects"
the small ring to be closer to the big ring. This isn't the first time
I've seen or encountered this problem. Previously I asked the crank
seller (V-O) about this situation, but was told they'd never heard of
it. But I believe I have seen reference to "9- and 10-speed spacers/
washers" for these cranks, I think at the Rene Herse site. It would
make sense that a narrower chain would need its chainrings closer
together than a 6/7/8-speed chain. Does anybody have any knowledge of
such spacers / issues?

Here's a blog report from today with photos, plus my review of the
Garmin 310xt GPS watch / computer / thingamajig, including a link to
the Garmin Connect page about the ride with map, elevation profile and
much more:

http://www.xo-1.org/2010/06/rough-riding-north-eastern-san-diego_19.html

Yours in sport,

Chris Kostman
La Jolla, CA
http://www.adventurecorps.com

http://www.the508.com
http://www.XO-1.org