Experienced IM Question---Bike Leg

I've only done ONE Iron distance race, so I don't know if I qualify as "experienced" but I do have an opinion....

I wore my most comfy and hi-tech padded shorts I own (Pearl Izumi UltraSensor).  At that distance the small amount of time it takes to change from tri shorts to cycle shorts is unimportant.  I guess if you're trying to qualify for Kona then time may be more important. 

As far as compression shorts under cycling shorts.....I've never heard of that.  I would think it would take away from the effectiveness of the padded insert.

When is your race? Have you done a 1/2 before?

I've only done one IM as well, but here is my experience:

I wore my tri top and tri shorts under my wetsuit. I switched to bike shorts for the bike in the change tent. I had to change again to running shorts for the run. My butt was used to the saddle from training, but I wanted to be sure.

When I do my next one I will wear tri shorts the whole race. If you practice in your tri shorts and your butt is used to long rides (100 miles) then you'll be fine.

Race how you train.

My suggestion is to practice in what you want to wear.  Your body will need to get used to the shorts you choose.  I would go with at least some padding.  It is a long day in the saddle.  Then are you going to run in them or change into running shorts.  If you choose to run in your biking shorts, you had better get some training runs in them as well.

Best of luck!

Yes, I wore my Tri shorts under my westsuit, but changed into the cycle shorts in the T1 tent.  And yes, all IM distance races (to my knowledge) have changing tents.

Some have made a good point about tri short comfort in the aero position.  I found this to be true as well, but opted for the more cushy feel of full-on cycle short for this distance.

Practice being wet in the shorts, see if there is any rubbing that is associated with the crotch/padding being wet.

Remember you will probably be wearing tri shorts under the wetsuit, also during the ride, you will be pouring water over your body to cool (if it's hot out) down.

So if you do change to Bike shorts in the Transition tents, get them wet during the ride and see if they chafe when wet.  People on the course will have water hoses for you to ride through.   Better to know in advance what it will feel like if wet.

   I've tried 3 different brands of Tri Shorts, and like De Soto the best with Pearl Izuma next best.

Same.  I use Oomph shorts, which just have a thin neoprene pad.  I train in 'em and I race in 'em.  Once you get enough Time In The Saddle, you don't need a laz-boy feeling of comfort.