Derailleurs, long, medium and short...What gives?

[h4tch3t]

Lo all,

Wanted to know what the real and true differences are between the bunch of lengths in rear derailleurs(other than the lengths). I have read some posts with some rather interesting information and even some mathematical way of figuring out which to use.

 

Keeping in mind that the purpose is not only to shift gears, but also to take up slack in the chain, I can't help but think that there's more to it.

 

Any takers?

 

Thanx

 

 

 

 

[Johan Bornman]

The longer the derailer, the more chain slack it can take up and thus the bigger difference between largest and smallest sprocket it can handle.

 

The mathematical formula you mention is the way to determine your maximum available number of teeth for a given derailer. Shimano is always conservative and you can squeeze two more teeth in than they claim.

 

 

 

[Super_mil]

See http://forums.mtbr.com/showthread.php?t=205890 for a good explanation.