HardwareLust said:My gf is not happy with her Shimano 105 Triple road bike. She says that she
would like some gears "like on her mountain bike" (Cannondale Jekyll with
LX/XT mix).
I believe the largest rear cassette that I can use with the Shimano 105
derailleur is 12-27
That's the Official Party Line. For the truth, see:
http://sheldonbrown.com/capacity
Quoted message said:(which she has now), leaving her with a 'granny' gear of
30-27 using the small chainring up front.
That's hardly a "granny" gear.
Quoted message said:So, my question is, how can I install a larger cassette, like a mountain
cassette?
Yes, that's one option.
Quoted message said:Can I put an LX or XT derailleur on the back and an LX/XT
cassette? Will that work well with the 105 STI levers?
Yes, but those will have uselessly high high gears. You might want to
consider one of my custom cassettes: http://sheldonbrown.com/harris/9
The stock 105 rear derailer will usually actually handle up to a 30 tooth.
Quoted message said:Or, can I get a smaller chainring for the triple up front?
Yes. See: http://sheldonbrown.com/harris/74
Quoted message said:What would make more sense? I
can easily afford the parts and the time to install them, so cost really
isn't much of a factor.
I'd suggest starting in front, put on a 26 and see if that does the
trick. If that doesn't go low enough to suit her needs, then it's time
to think about a new cassette (and a new chain to go with it.)
Quoted message said:(Obviously, what would make the most sense would be to convince her to RIDE
MORE, so that her legs would be in better shape, but that's a different
discussion entirely. :-) Either that, or throw some slicks on her MTB!)
Yes, a discussion that you would be better off NOT starting with her.
Sheldon "Low Gears Are Good" Brown
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| How harmful overspecialization is. |
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