Triple or Double?



rt1965 said:
Well, I've already bought the bike and I did have it converted to a compact double. They did have to change the front derailer, and the shifter on top of the crankset. All is well, the bike is fantastic. I am going back tomorrow for a full fitting.
I think it's also be worth your while to buy a 12x25 or 12x27 rear casette for really hilly rides.
 
rt1965 said:
Well, I've already bought the bike and I did have it converted to a compact double. They did have to change the front derailer, and the shifter on top of the crankset. All is well, the bike is fantastic. I am going back tomorrow for a full fitting.
I presume that the reason you want to train in the Flagstaff area is to get away from the HEAT!

FWIW. This is after-the-fact since you just mounted the compact crank on your bike -- I just (as in, over the past weekend) mounted a cassette with an 11-32t cassette in a frame with a short cage 105 rear derailleur & 52/39 double crankset -- the center of the particular derailleur hanger bolt is 3cm from the axle center -- the short cage rear derailleur (to MY surprise) has enough capacity to handle the chain. That's a pretty low combination which I know is good enough for riding on mountain roads; but, obviously not quite as low as with most triple setups. You may never need to use anything larger than the 28t in the cassette, but the 32t will be a good bail-out cog to have in reserve.

While it isn't as good as having a compact crank, you could always mount a 38t 130BCD inner chainring on a standard road crank; so, I would certainly try a cassette with a 32t cog before opting for the triple ...

If you run a slightly longer chain which can accomodate the 52t-or-53t chainring & 32t cog, then you can just swap cassettes as needed ...

FWIW2. Unless you are planning on riding EAST, SOUTH or WEST of Flagstaff, it's probably FLATTER than you think/remember ... it seems pretty FLAT (to me when I am IN A CAR) as you head NORTH to the Canyon. It will probably be WINDY ...
 
alfeng said:
FWIW. This is after-the-fact since you just mounted the compact crank on your bike -- I just (as in, over the past weekend) mounted a cassette with an 11-32t cassette in a frame with a short cage 105 rear derailleur & 52/39 double crankset -- the center of the particular derailleur hanger bolt is 3cm from the axle center -- the short cage rear derailleur (to MY surprise) has enough capacity to handle the chain. That's a pretty low combination which I know is good enough for riding on mountain roads; but, obviously not quite as low as with most triple setups. You may never need to use anything larger than the 28t in the cassette, but the 32t will be a good bail-out cog to have in reserve.

Actually that 39/32 is very, very close in roll-out to the 30/26 which is my bottom gear on the triple. I should have thought of that solution before I invested in converting to the triple for the mountains! Got to say I wouldn't have wanted anything any higher in the Alps a couple of weeks ago. I really thought the 30/26 would give me a couple of bailout gears, but in the end the climbs are so long (Joux-Plane was 12km straight up) that I spent most of my time in bottom gear and if I'd had another couple of lower gears I'd have used them too! But I like to spin rather than mash, so a masher might have found my gears too low.