Compact gearing choices and chain wrap question
07-01-09, 08:16 AM
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Compact gearing choices and chain wrap question
Hi~ I have currently the following setup:
Campag 9 Speed Record rear mech with short cage (RUNNING 10 SPEED btw)
11-25 Cassette
50/34 chainrings
I believe I have too long of chain wrap for my rear mech (30) and need a medium cage for better shifting and possibly less cross chaining. So, here are my many questions....
1. Generally how much longer of a chain is needed for going from short to medium cages?
2. What parts besides the two halves of the cage do I need for the rear mech? I assume I can go Chorus instead of Record for $$ savings?
3. Is anyone here running this setup, meaning medium cage, 10 speed 11-25 50/34?
Thank you for your help!
-solarpos
Campag 9 Speed Record rear mech with short cage (RUNNING 10 SPEED btw)
11-25 Cassette
50/34 chainrings
I believe I have too long of chain wrap for my rear mech (30) and need a medium cage for better shifting and possibly less cross chaining. So, here are my many questions....
1. Generally how much longer of a chain is needed for going from short to medium cages?
2. What parts besides the two halves of the cage do I need for the rear mech? I assume I can go Chorus instead of Record for $$ savings?
3. Is anyone here running this setup, meaning medium cage, 10 speed 11-25 50/34?
Thank you for your help!
-solarpos
Last edited by solarpos; 07-01-09 at 08:27 AM.
07-01-09, 08:36 AM
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I advise you take this on the mechanics section. Very helpful guys out there. Someone may give you a hard time here for using Campy. 
07-01-09, 09:19 AM
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And how would that be a problem?
I am well aware that the internetz are full of tough guys, usually 132 pound skinny roadies ready to pounce upon any unsuspecting victim with thin skin. Ah the safety of a keyboard and monitor!
07-01-09, 12:31 PM
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The short cage rear derailleur is fine with the 50/34 and 11-25 combo.
Remove the chain from the rear derailleur put in on the large / large gear combo without the derailleur find were the link fits then add 1 link.
Install it as it should be and your set.
Remove the chain from the rear derailleur put in on the large / large gear combo without the derailleur find were the link fits then add 1 link.
Install it as it should be and your set.
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It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
07-01-09, 12:38 PM
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"Remove the chain from the rear derailleur put in on the large / large gear combo without the derailleur find were the link fits then add 1 link."
+ 1, that method for determining chain length is pretty accurate
+ 1, that method for determining chain length is pretty accurate
07-01-09, 01:33 PM
#8
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The better way to set the chain length is in the small/small combo. This insures the maximum wrap capacity for any RD. Set it to the maximum length that creates some tension on the chain when the ends are brought together. The lower pulley will swing down slightly, but the chain should never hang loose or rub on the upper chain guide tab.
The big/big method is OK if you've got the largest rear cog that you will ever use on the bike, but it can still produce an ambiguous result. If the ends brought together are both inner or outer links, the chain can't be put back together, adding 1 inch. To be safe, add 1-1/2 inches or 3 links, but you should still double check the little/little - which is the better way to start with.
The short cage should work OK.
FWIW, I've got one bike setup with a 50/34 and 11-25 10 speed with a medium cage RD, but the medium is not needed. I had a triple on that bike and needed it for that setup.
I've got two bikes with 11 speed, 50/34 with 11-25 too. The only choice is short cage RD, since there is no medium cage yet.
The big/big method is OK if you've got the largest rear cog that you will ever use on the bike, but it can still produce an ambiguous result. If the ends brought together are both inner or outer links, the chain can't be put back together, adding 1 inch. To be safe, add 1-1/2 inches or 3 links, but you should still double check the little/little - which is the better way to start with.
The short cage should work OK.
FWIW, I've got one bike setup with a 50/34 and 11-25 10 speed with a medium cage RD, but the medium is not needed. I had a triple on that bike and needed it for that setup.
I've got two bikes with 11 speed, 50/34 with 11-25 too. The only choice is short cage RD, since there is no medium cage yet.
Last edited by DaveSSS; 07-01-09 at 01:36 PM.
