Originally Posted by
swampy1970 .
The length of the climb and the relatively shallow grade isn't what's gonna get you. The altitude will. I think the low point of that ride is 7,000ft and there are sections over 11,000ft. Even with fresh legs, 10,000ft to a sea level flat lander is an immediate 20% or more hit of sustainable power and at worst altitude sickness and easy dehydration if you don't keep up with the fluids.
Your "bail out" gear should factor in all worst case senarios.
Altitude and all the weird things that happen*
Fatigue from riding all day.
Some degree of dehydration.
Bonking.
More sustained climbing than you're used to.
Possible dietry "consequences" from eating/drinking stuff on the bike that you may not be used to consuming.
* - my personal experiences with altitude. Headaches, dizziness, dehydration, vision issues (road in peripheral vision seemingly travelling at a different speed than the section of road I'm staring at) ears plugging up on descents (like some people get on aircraft landings/takeoffs) that mess with your head going around corners, hand/foot swelling. Altitude can severely effect your ability to sense when you're hungry and thirsty
Any one of the above will probable get you riding the next cog up from the one you normally ride. Any two of the above may be a ride ending event or at least two cogs bigger (32 instead of a 25 - on a cassette ending 23,25,28,32)
Based on your other thread, you should just put on your hyper climbing, "I will drop you all - I am Pantani reborn!!!@!" Easton carbon wheels on the bike.
If your Specialized frame isn't the "team module" and doesn't have the BB30 bottom bracket then you can pick up a compact chainset for pretty cheap. I picked one up for the Alta Alpina Challenge (200 miles, 8 passes, 21,000ft climbing) to temporarily replace the >5lb PowerCranks - a SRAM something or other for $60 inc bottom bracket. 50/34, looked OK and worked as intended. A quick 20 minute swap and the bike was much lighter. If you do have a BB30 bottom bracket shell then you're looking at $250 and up for a new chainset and are stuck with something from SRAM, Truvative, Specialized or Cannondale. The last two are very expensive - but very nice.
For long cage rear mechs and cassettes - there's always the SRAM Apex. It seems to be well priced and has an 11-32 cassette and a rear mech that'll work with it and your SRAM red levers. Apparently it was good enough for Contador to use on the Giro last month...