A truck.

Activity | TrainingPeaks

939 watts to catch the draft.

223 watts to sit in the draft at 39mph.

Unfortunately the fun was short lived when we came to the end of the development.

Great fun ! Unless the truck driver slams on the brakes. Then you become a decal on the back of the truck.

Aero trumps weight after all...

Someone has seen "Breaking Away" once too often........

Child's play.
https://youtu.be/iO7_Fq56g2c

you can out brake a truck. and the draft is strong enough that you can leave 6-8 feet of space.

Also helps to get over to the side occassionally where you can look up the road. and keep very careful watch on the brake lights.

Did you get any KOMs? I've heard they are very prestigious.

I have a seen a youtube video of riders behind a truck going very fast. Looks like it could be fun but my fear of life-threatening stunts would keep me from ever trying it.

Right. You could be the guy on YouTube doing 55 on the flat on his bike, or you could be the guy slamming into the back of a truck at 55 mph on a bike. Risk >>>reward.

1986 Plymouth Horizon with hatch back up and wife driving in Rotonda West, flat as a pancake and 45mph+ back in 1987 on 1983 Paramount. It was fun.

Yeah, that's pretty impressive, or insane, depending on how you look at it.

Fastest I've gone motor pacing is 55 behind a tractor trailer.

The 39 mph in the link I posted is no big deal.

The point the data illustrates which is somewhat striking, and why I posted it, is how big the aero advantage is. With no draft, 39.1mph under the conditions prevailing would have required around 1400 watts.

Instead my peak power was 939, which was mostly accelerating into the draft as the truck past me, and then it only took around 220 watts to hang out in the draft.

It's actually pretty cool seeing some real data on the difference in wattage required, I was just busting your chops.

I've been grabbing free rides for 40 years, when opportunity presents.

Never done a Davis Phinney impersonation. Worst thing that ever happened to me was double pinch flat hitting a massive pothole that the SUV I was drafting stradled.

Learned form that to only do it on roads I'm familiar with and have good pavement.

I wanted to try it on the 7-mile bridge in the Florida Keys but my aversion to dying always seemed to get in the way...

I also draft when I get a chance although I'll usually hang out on the corner. Don't get as good a draft but I have an easy exit route if needed.

The only time I had a problem drafting a semi was when I was inattentive and following too close in a car and didn't notice the semi swerving around a 4x4 laying across the road. Hit it with my front wheel and cracked the rim but didn't lose air in the tire. A $400 mistake but could have been worse on a bike

Jose Meiffret used this bike...



...to draft a Mercedes 300SL on the Autobahn...



...and achieved 200KPH (127MPH).

Date with Death

On a group tour last May, another guy and I wanted to go visit a place that was about 25km away, while everyone else relaxed after a day of climbing a mountain, but we were afraid we couldn't get there, look around, and get back in time to clean up for dinner. So the guy who drove the van escorted us the whole way. We didn't go particularly fast, and we probably didn't stay as close as we should have to get the best advantage, but it worked out well - he was a very good and careful driver, and we made great time without breaking a sweat.

Jumping into a draft is a lot like catching a wave. Quite a rush.

20 mph is 29.33 feet per second. If the truck slams on the brakes and you are really sharp, you might be able to react in 1/4 of a second, maybe. That's best case scenario.
You travel 7.3325 feet in that 1/4 of a second at 20 mph. You hit the truck before you move your hands to the brakes. At only 20 mph. There's no chance of not hitting the truck. Most people don't get this either. If you glance at something else the reaction time is much longer.

I'm not saying I never draft a vehicle, or that it's likely the truck slams on the brakes. But it's good to know the risk. If the truck slams on the brakes, you have a really bad day.

assuming the truck somehow comes to an instantaneous standstill............

I don't see the benefit. Isn't the workout obtained by exerting 900 watts a better workout than from exerting 200 watts?

The new natural gas powered buses are good for a draft. No fumes and they start out slow enough to not pull a gap on you.

Sure it shows the benefit of a draft, few would dispute that there's a benefit. But the draft from a truck is hardly comparable to the draft from a cyclist.

Highway scene:

https://vimeo.com/50872582


It's a good movie to watch if you want to learn how to repair a tubular on the side of the road

Glad someone else noticed that.

Still, I've drafted trucks/vans before when they've passed me on relatively quiet roads, but only on the edge of the draft where I can still lean out and see what's ahead, and swerve off to the side if they do try to panic brake for some reason. It just seems unnecessarily risky to sit in a blind spot unless you know/trust the driver of the vehicle and know the road surface.