Originally Posted by gcl8a
Then you're not riding hard enough.
80k. Stop at bakery. Take off helmet. Eat pastries and milk.
Hot head + Clammy, sweaty helmet = Mr. Helmet rides home on the bars.
If you say it looks good for the photos, even better. Don't forget to zip up.
Then you need to get a better helmet or ride faster yourself. At reasonable speed a good helmet will funnel enough air over your head that heat won't be an issue. The exception to this is of course mtbing and occasionally really steep road climbs where you are moving 5mph for an extended period.