|What do these Campy Derailleur specs mean?||Inhighgear|
Dec 3, 2002 7:49 PM
|This is from the campy site for their new 2003 Chorus triple derailleur. One has a medium cage and one's has a long cage. They both will allow a rear 29 cog but what does the difference in Cap. 36 vs 39 mean?
min. sprocket 12 - max. sprocket 29 - cap. 36 - max. front diff. 23 -lightened upper body.
min. sprocket 13 - max. sprocket 29 cap. 39 max. front diff. 23 lightened upper body
|Cap 39 will take 39 tooth difference..||Spunout|
Dec 4, 2002 4:32 AM
|so that you can use the 13-29 and a 30 tooth granny. The medium cage should be used with a cogset no larger than the 26 with triple. I have a medium cage to use with 13-29 and a double chainring.
Capacity: Refers to the chain wrap from the small-small combo to the large-large. So, with a 52+29=81 large and 30+12=42 small (not that we'd really use those combos because of the chain-line) we would require (81-42)=39 capacity rear mech.
Cool or what!
|Cap 39 will take 39 tooth difference..||Inhighgear|
Dec 4, 2002 4:58 AM
|Very cool...Thanks very nice explanation.|
|cool but not quite correct...||C-40|
Dec 4, 2002 8:16 AM
|Total capacity is calculated by adding the difference between the chainrings and the difference between the cogs.
In the case of a 52/42/30 triple and a 13-29 cassette the needed capacity is (52-30)+ (29-13) = 38.
|And I'm not quite wrong...||Spunout|
Dec 4, 2002 9:37 AM
While you wrote:
Dec 4, 2002 11:50 AM
|You're right, you get the same answer either way. Just seems like an unusual method to derive the answer.
My method seems easier to do in your head. A 22T difference up front and a 16T difference in back adds up to 38.