Moved to Colorado Springs 6 weeks ago, and am planning to make my first attempt at pikes peak (before the race/ride on August 24th). The climb is 20k long, and goes from about 7,000 feet of elevation to 14,000. I have a compact crank and an 11-27 cassette now, and it works well for most climbing around here, but I have never done a single sustained climb like this before. I have done rides of up to 6,000 feet of climbing over 35 miles, but that is the most climbing I have done in a single ride here, and none of that got me much above 7,500 feet of elevation.
Has anyone here done the climb, or of you haven't, still have any recommendations for what would be reasonable cassette for a (formerly sea level) midpack cat4 racer with a compact crank?