I'm an early-30s San Francisco, CA based MOP triathlete. Fairly strong swimmer/runner and relatively weak rider (3.0 watts/kg weighing 70kg) with mediocre bike handling skills.
I'm looking for some gearing advice as I enter the final stages of training for IM Canada this July. This is my second IM, with previous being IM Louisville at 6.5 hour bike leg. Consensus for the old IM Canada course seems to be that a compact + 11/28 is ideal for most riders. I'm not sure if new course announced for Whistler this year changes this guidance.
My bike: Canyon Ultimate 9 SLX Pro, Campy Record 36/52 x 12-27 running Bora 50s.
So question is: What should I do with respect to gearing. Easiest fix is dropping on 12 x 29 cassette. Alternatively, I could swap to a compact and run the 12-29 (or perhaps an 11-29 to get back some of my top end), but that's obviously a bigger upgrade. I presume both options will require a new chain.
At the end of the day, cost isn't really an issue, especially since I could recoup much of the cost of a new new crank by selling my old one. I just want the best setup for least hassle that will leave my legs fresh enough to finish the marathon and be versatile enough for my shorter course races.