First thing that comes to mind is durability of your glide wax.
Normally, kick wax wears and so glide improves over time. What did
you do to prepare glide zones?

rm

wrote:

I am new to waxable classics this year and used them for the first
time at the Canadian Ski Marathon and the Keskinada. I seem to be
able to wax well for a decent kick (at least I was able to get up the
hills fairly well) but at the Keski my glide was poor after the first
10K or so.