Originally Posted by waterrockets

I chase trucks all the time. I've had some 5-minute draft sessions, and I've been over 55mph behind them for significant stretches. I've never had any issues with probably 70-80 drafts/year for 19 years of road cycling.

For those who are worried about hitting the truck, that's not always going to be a problem. I used to draft a team van with some other teammates, with the back doors open. The van was all white, and we used to put skid marks on the rear bumper at 45mph, trying to make patterns or long streaks. Hitting a truck really hard, or hitting an edge of an angle-iron bumper will... umm... "complicate" things a bit, but it's not like you explode if the front tire touches the truck.

The biggest hazard is debris that the truck runs over and throws into you, or you run over it yourself. For this reason, I stay behind a mud flap, and every 10 seconds or so, I pull out and look waaaaaaayyyy up the road, to see what's up there. I've only seen one hazard doing this, but I'm glad I did. Just a big pothole, but it wouldn't have been pretty at 58mph.