ClarkinHawaii

I'm currently seeking the best way to mount my taillight. Could you post a few pictures of your mount showing how it's constructed/mounted? Thanks.

cyccommute 

It is not an issue with clamp-on derailers which are, by far, more common than braze-on hangers. I have a Tiagra shifting a 46/34/20 crank and an Ultegra shifting a 48/36/26 crank. Neither has any problems. Before I got the 46 tooth outer, I was using the Tiagra to shift a 44/34/22 and still didn't have a problem. The radius of the derailer and the length of the derailer are non issues. All of these shift nice and crisp

Additionally, if the bike were set up with a braze-on for a compact double, it would likely work with a 48 tooth trekking crank. There should be enough movement in the braze-on for that kind of difference.

If you are coming to Colorado from a low altitude, training on hills may help your muscle strength but it does nothing for lung capacity or for the blood's oxygen carrying capability. Riding a bike with a high low gear requires more oxygen to your muscles and your lungs aren't going to provide it if they don't have the capacity to deal with the lower air pressure here. A lower low gear allows you to do the same work with less effort so the oxygen requirements are lower. Short of riding in a pressure chamber, there's really no way of increasing lung capacity or red blood cell volume other than riding at altitude. But those changes take weeks, months or years.

Shimagnolo

You don't necessarily need to *train* at altitude, but just *live* at altitude to get the hemocrit level up.

Other options:
a) Sleep in a hypobaric chamber.
b) Sleep in a room with air processed by a machine that lowers O2, while increasing N, and scrubbing CO2.
(There was an article in Outside magazine about this a few years ago).
c) EPO.

Al1943

I believe that is no longer true. Over the last 15 years I have purchased 9 new road bikes for my family built by 3 different companies. Seven have been equipped from the manufacturers with braze-on type front derailleurs. It has not been possible to lower the FD's on any of these to fit anything smaller than a 50 tooth big ring. On my wife's Trek 5200 I ground down the bottom of the derailleur hanger enough so that we could install 49-39-30 chainrings.
Most carbon fiber frames and many other frames are equipped with braze-on type FD's.
Newer bikes with varying shaped frame tubes create problems with trying to lower clamp-on FD's.
Several forum posters have reported issues with trying to lower FD's enough to run small chainrings.
I think it is very irresponsible to imply that there is no problems changing cranksets and chainrings to smaller sizes without knowing more about the front derailleur and seat tube.

cyccommute 

It is equally irresponsible to imply that there is a wide spread problem changing cranksets without knowing more about the front derailer. The majority of bikes still come with clamp on front derailers and a large number of them come with compact cranks. The best that AS2914 can do is to try it. If it doesn't work, there are other options.

AS2914: Check to see if you have a braze-on derailer. Even if you do, you may not be sunk. Just see how much adjustment you have left. Since Al1943 is concerned about the diameter of you seat tube (if you have a clamp-on derailer), check the diameter for 10 to 20 mm below the current clamp. If the diameter is the same, you are good to go. If not, you can always go to a "normal" road triple, i.e. a 52/40/24 tooth crank and a lower rear cassette. You'll need a mountain bike rear derailer for a anything over 30 teeth.

cyccommute 

Training helps a lot Your other options are either very expensive or possibly deadly

Al1943

Humm... is that a paradox or a contradiction?

AS2914

Update

I bought a truvativ 52-42-30 triple crank off of eBay
It came with a gxp bb that will also work
With my SRAM compact rival crankset.

I installed the truvativ today using the existing bb.
I was surprised to find out I did have to touch the FD or cable
Tension. It shifts perfectly! The only thing left to do
Is remove the 12-25 cassette and install the 11-28

I might have to change the chain, but I'm confident
The 30-28 will work for me in the mountains and 42-11
Will be ok in the flats

Thanks for the input

Camilo

If you're a flatlander and also plan to ride mountains from time to time, you should just bite the bullet and convert to a road triple outfit.

The road triple will give you both the higher gears you might like to have on the flats and going down hill in the mountains. It also will give you substantially better low gears for the mountains than any compact double. Unfortunately, there's no cheap solution, because what you now have is about as low as you can go with a compact double and a normal rear derailleur. Your minimum change will be to a very wide range, low MTB cassette and a new MTB type rear derailleur.

Ranger63

TA 33t Chainring?
Harris Cyclery has em.
Ramped and pinned and for 110BCD
Unsure how much the one tooth difference would help.
I know I tried a 30t using the 105ss that came with the PDG and...it didn'thappen regardless of how much I tweaked.