Campy Record rear derailleur capacity question

On 27 Jun 2004 07:45:39 -0700, [email hidden] (Eagle

Jackson) said:

Will a Record medium cage derailleur work with a compact (50-34) crank
and 13-29 cassette? Or do I have to go to a long cage?

IT will work fine as will the later vintage, standard cage rear
derailleurs.

Eagle Jackson said:

Will a Record medium cage derailleur work with a compact (50-34) crank
and 13-29 cassette? Or do I have to go to a long cage?

Yes and no.

A couple of days ago I removed a 53/39 on a 13/28 bike with
Campagnolo short changers, bolted on the customer's
requested 30-40-50 triple ( same BB). It shifted acceptably
for that customer but not acceptably, in our opinion, for a
new bicycle.

Since you own the medium changer, apparently, go ahead and
change the crank. Then decide if the loss of the 34-15 from
chain sag bothers you enough to buy a derailleur.

Derailleurs have ratings, which you will exceed, to allow
use of all gear combinations. Specifically, one _should_
change to a medium here, but since you apparently don't
want to, you don't have to - you'll get full use of the low
and high gears. Just not some of the near-crossover
combinations.

Since we are only the bearers of this news and find
ourselves at the short end of some hostility over it, I'll
close with this:
There is some risk of the chain catching on the outside
bottom edge of the rear changer's cage in the 34-13,
wrecking the changer and the frame. Shortening the chain to
avoid that trades 'possible failure' for 'impending doom'.

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

On Sun, 27 Jun 2004 16:03:30 -0500, A Muzi <[email hidden]>

Quoted message said:

A couple of days ago I removed a 53/39 on a 13/28 bike with
Campagnolo short changers, bolted on the customer's
requested 30-40-50 triple ( same BB). It shifted acceptably
for that customer but not acceptably, in our opinion, for a
new bicycle.

With 50/34 the chain usually gets short enough so that it won't tick
the underside of the rear derailleur in 50/13. With the newer, short
cage varieties, the upper derailleur pulley will not hit the 28 in the
34/28. In all cases, you can wrap the 50/28.

My wife's bike, 48/34 x 13/29 uses a 9sp std. cage Record rear
derailleur. I had to mount the 'b' tension screw on the inside to get
the pulley away from the 29 in 48/34.

My 2 bikes use up to 13/29 with 50/34 with newer front derailleurs
with no problems. Coincidently, my chain and my Caryl's are the same
length. Both Cannondales 56 and 49 cm.

Were I buying new parts, the Veloce rear derailleurs work fine.

The only bicycle that needed a longer rear derailleur was the tandem,
50/34 x 12/34.

A Muzi <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Eagle Jackson said:

Will a Record medium cage derailleur work with a compact (50-34) crank
and 13-29 cassette? Or do I have to go to a long cage?

Yes and no.

A couple of days ago I removed a 53/39 on a 13/28 bike with
Campagnolo short changers, bolted on the customer's
requested 30-40-50 triple ( same BB). It shifted acceptably
for that customer but not acceptably, in our opinion, for a
new bicycle.

Since you own the medium changer, apparently, go ahead and
change the crank. Then decide if the loss of the 34-15 from
chain sag bothers you enough to buy a derailleur.

Derailleurs have ratings, which you will exceed, to allow
use of all gear combinations. Specifically, one _should_
change to a medium here, but since you apparently don't
want to, you don't have to - you'll get full use of the low
and high gears. Just not some of the near-crossover
combinations.

Since we are only the bearers of this news and find
ourselves at the short end of some hostility over it, I'll
close with this:
There is some risk of the chain catching on the outside
bottom edge of the rear changer's cage in the 34-13,
wrecking the changer and the frame. Shortening the chain to
avoid that trades 'possible failure' for 'impending doom'.

Thanks, this is very helpful.

eagle-<< Will a Record medium cage derailleur work with a compact (50-34) crank
and 13-29 cassette? Or do I have to go to a long cage? >><BR><BR>

Will work fine. As a matter of fact, so will the short cage.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

I had this setup and the 13-29 hit the top of the derailleur. It was not
enough to effect shifting really it just made a chainsaw noise (my opinion).
It was really only a problem for me and the fact that I just spent a small
small mint on the bike......I went with a small cassette and the issue was
resolved.

I am using a med cage Derailleur by the way.

Biff Stephens

"Eagle Jackson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Will a Record medium cage derailleur work with a compact (50-34) crank
and 13-29 cassette? Or do I have to go to a long cage?