Originally Posted by
Kevinti
So with a 36 on the cassette are you guys running mountain bike derailleurs with extra long cages? Seems like with the road stuff I have been looking at a long cage is good for up to a size 34 cassette, and I bet I would need to be more compact on the chairing too! hmmm
I guess so. Never thought about it. The Raleigh Coupe we have is a Road tandem and the crankset was 53/42/30 and the cassette was 12 - 27 9sp. Both derailleurs were Shimano 105 MTB. The cage on the rear is seriously long, but the main reason why mountain stuff exists is because the topmost jockey wheel of a Road rear derailleur will hit the big cog of a cassette when the tooth count gets much above 34/6.
There are extra long hangers that will allow a standard Road derailleur to clear a 36T big cog, but a long cage is still needed, even with a 12 - 27 or 11 - 32 when used with a Road Triple. When you swap the 30T granny for a 26T or 24T like we did, you
must have a long cage, and even then you will void the warranty, although I haven't found that anything bad happens from going so far out of spec. I haven't run the numbers but, yeah, rather than try to find a 13 - 36 Unicorn, it would be better just to swap the granny. 24T grannies are available for a song because they don't need to be fancy. No ramps, no pins, no narrow wide or wave cutting of the teeth. Just a plain old chainring. I think I paid $9.99 for the last one.