IMOO Which wheelset/cassette??

IMOO 07 was my first Ironman and I live and train in upstate NY where there is no shortage of hills. I learned a good lesson last year at Moo in that I got a little big headed and went with a 11-23 cassette. I actually has a 12-25 on the wheel and after driving the course with another BTer thought that I could hammer the downhills in the 11 and not need the 25 on the uphills. It looked good on paper. The first loop the plan worked well and I was having a great ride. When I got to the two big climbs on the second loop I was wishing I had that 25 (or a 27 for that matter).

I used my Mavic Kyserium Elite on the front and a disc on the back. If you're a strong cyclist I would recommend a 12-25 or 12-27 for a cassette. What worked for me in KY this year was to take the uphills easy and keep my HR down and accellerate as you crest the hill and push the downhills and flats.

Most of all ........ Have a blast!!!

I used a 12-25 in KY and had a great bike leg. 12-27 would be good insurance if you are not a hill climber or don't have hills to train on. It's worth taking it easy on the uphills and not burning your legs out because those hills just keep coming at you.

I totally agree with Bob on this one.  I had a 12-27 this year at MOO and was happy.  I didn't get into the 27 until the last two climbs (second time around), but it was nice to spin.  And I kept the watts steady for the ride, and got to still put pressure on the 12 going down the hills. Once I reached 40mph or so, I recovered.  Or went to the bathroom

Bottom line is the 27 is nice to have, and doesn't hurt in the overall scheme of things.