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Hi there,

I'm a mountainbiker and, after a long struggle, am finally mentally ready to get a road bike for complementary road training (as well as for some leisure riding); I usually ride on my own and hardly ever in a big bunch. What I'm saying is that I don't intend to become a dedicated "roadie". Perhaps I will take part in a couple of iconic races a year, but more for the sake of their social side and as motivators and fitness tests rather than to seriously compete for top trophies.

My question pertains to the gearing I should have on my bike. I've already figured which bike I'd like => Giant TCR Composite 2. It comes with a 10-speed 11-23T cassette and a double ring 39-53T crankset. The thing is that I've no experience with bikes of this sort, thus am not sure whether such aggressive gears are appropriate considering: first, intended use as indicated above; second, that New Zealand roads are often hilly, with up-hills being steep and long; and finally, that Wellington is a very windy place, and riding against strong head-wind is a real battle where I absolutely appreciate soft gears of my MTB allowing me to spin with high cadence.

To the point. I seem to have four options:

(1) leave everything as is

(2) change the crankset to a triple ring 30-39-52T

(3) change the cassette to 12-27T

(4) do both (2) + (3)

Hard-core roadies tell me "you don't need this / your legs will condition", but my thinking is:

Re (1) -- may be just too stiff

Re (2) -- I like this idea the most, but a mechanic at my LBS told that it would be a messy refit and that he wouldn't be keen to do that for me

Re (3) -- that's what the said mechanic recommended to address my concerns re (1), the downside being greater increments between gears [not sure which would give a greater total range, (2) or (3)]

Re (4) -- perhaps an overkill

What's your experience, guys? Many thanks in advance!

-Tomasz
 

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First of all you need to realize that you don't need most of the incredibly low gears you find on a mountain bike. Rolling resistance is much lower on the road with 23mm tires so you can push heavier gears more easily than a mtb. I'd say leave the bike as is. The only thing I'd change is the cassette for a 12-25t. An 11-23 is a pretty agressive cassette better suited for hard sprinting and hilly roads with no major climbs. A 12-27 is a bit too much. The 27 really just becomes a huge bailout gear. Going to 27 will also require the rear derrailleur to be changed to a medium cage from a short cage. A 12 - 25t is a perfect ratio for all around training. Don't consider a triple chainring. If your purpose for getting the road bike is to improve your fitness going with a triple to have a 30t bailout gear is not going to help you improve at all. Just about any climb can be done on a 39X25 gear. You might really have to suffer on some of the hardest ones but thats all part of the idea right? :cool:
 

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I ride a 39/53 and 12-25 (9 sp) combo myself. I usually don't do long sustained riding in the mountains (use it mostly for my backyard rides here in the SF Bay Area, which has some good hills), but I have climbed a fair amount on it and you'd probably do well with it at least to start with. Like Hecubus says, this is an easier change than one involving a new rear derailleur.

While triple cranksets are one way, you can also think about using one of the smaller 110 bcd cranksets now becoming popular in the roadie world to achieve different gearing choices; with the 130 bcd crankset you aren't going to find a chainring smaller than 38t, but more choices with the 110 (38/48 is popular, for example) While this is going to require a new crankset, it doesn't require a new front derailleur or shifter (well, depending on equipment that comes on your bike, these might be needed). It's really fun having a 53x12 to descend with once in a while, though!
 
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