Cycling tights - confused!

[beccaB]

Becca,

I've gone so far as to wear long johns (both silk ones and more high tech ones) over shorts and under biking tights.

You're sure the hives aren't more a heat rash?

Yes, I never get them in warm weather, and it's always when I am starting out really cold. It's red with welts and little bumps underneath.