MythBusters - Drafting a Semi

[ucantcme]

http://www.youtube.com/watch?v=lttgT1XZVvE

Check it out. Time to move on into the 10ft area!!

Only kidding of course. Saw this on YouTube and decided to spread the word!

[civic94]

that test is tested at 55 mph, and i rarely see semi's going that slow. besides, going 55 mph in most cars get very good mileage, anything after 55 is getting more and more worse


if they tested it at 70 mph, it would of been a bigger difference

[ucantcme]

Originally Posted by civic94

that test is tested at 55 mph, and i rarely see semi's going that slow. besides, going 55 mph in most cars get very good mileage, anything after 55 is getting more and more worse


if they tested it at 70 mph, it would of been a bigger difference

I've been behind a semi, actually on the way to work today, he was going about 57.

As the video said - How many semi's go 70? If anything they should have done the test around 60-65 area.

[ziddey]

drafting semis... good way to say bye bye to your windshield.

i was maybe 5 carlengths behind a semi today and still managed to destroy my windshield this afternoon.

[theholycow]

You were probably too close for a good draft. Read the drafting link in my sig...in that thread, it is mentioned that 3 times the length of the truck is appropriate, and that 3 seconds is the most effective distance.

[ucantcme]

Originally Posted by theholycow

You were probably too close for a good draft. Read the drafting link in my sig...in that thread, it is mentioned that 3 times the length of the truck is appropriate, and that 3 seconds is the most effective distance.

I have gained a lot of knowledge from the links in your sig. Thanks a whole bunch!!

[maxxgraphix]

It's hard to tell in a car. But on a bike you need to be very close to feel the difference. All I can say is that if the semi slammed the brakes you would face plant the trailer. I draft semi's when I need a rest when on my bike. I tend to stay at the edge so I could swing around if needed.

[Z man]

The semi trucks on the stretch of I-81 in West Virginia go 70mph or over usually, the speed limit is 70mph. I go 55-65 anyway. Haha.
It's difficult to keep up and draft them.

[theholycow]

Originally Posted by maxxgraphix

It's hard to tell in a car. But on a bike you need to be very close to feel the difference.

In my experience, no. A comfortable, safe distance draft really helps me go a lot further without getting so tired. Also, more appropriate when talking about drafting a car behind a big rig, drafting a group of bicycles or a slow moving car really works great.

You don't have to overlap wheels, or even ride so close that you can't look ahead for fear of having to stop suddenly. You don't feel the wind sucking you, you don't go much faster, but you save energy for sure. It even works for slow riders.

[99metro]

I watched this on Mythbusters. The guy driving said it was scary and very uncomfortable driving so close. Drafting semis less than 2 seconds away is an amateur's way to hypermile, IMO. There's nothing scarier than following an 8 foot wide by 12 foot high wall at any speed, not knowing when that wall is going to come to a sudden halt - and I really hope whoever is doing that is paying attention. It's sort of like those people that like to drive the speed limit in dense fog; you just don't know if a stopped car is going to come into view...

I don't ever want to exit my car by way of the windshield, and if I DID make it through in one piece, I certainly don't want to faceplant the very thing that forced me through the windshield in the first place.