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In the classic bicycle movie Breaking Away, the hero drafts a tractor trailer rig up to 60mph on a level road. Is that possible in real life? I've gotten to where I can't peddle any faster in top gear and I'd guess I was only going about 25-30 mph.
 

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"possible"

is a broad term. Sure it's theoretically possible, with the right gearing. The motorpaced bicycle speed record (on a special bike behind a race car with a special fairing on a long flat track) is over 160 mph. With the highest gearing common on road bikes (52x11), you'd need to turn the pedals at about 162 rpm to go 60 mph. Not many riders can do that with significant power. The inside joke FtF refers is the fact that Dave appears to be in the small ring in that scene in the movie -- which would require a clearly impossible pedal cadence.
 

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They need to do a mythbuster on shaving your legs.
 

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I have done it at 50....60 may be a bit scary. You need a downhill run in as you would be spinning in a 53x11

I used to live in Italy, not far from Lucca where Chipo is from. It seemed like every year right before the Giro or the Tour the cops would stop him and some teammates practicing lead outs on the Firenze-Pisa autostrada. They said it was the only flat straight place they could do it. They would motorpace with the team car up to speed then go full gas with a 54x11. Of course they always let him go.
 

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Yes. Back in 1994 when I was living in Chico, CA., I was really hardcore into downhill and drafting. I spent almost $100 on a “rare” (at the time) 12-tooth rear cog and then also acquired a 55-tooth front chainring for I believe $80 (quite cheap in comparison to the rear cog). Anyhow, any chance I got to draft was surely taken advantage of. I’d drafted behind many a semis on highway 32 (between Orland and Chico), and how I am still alive I don’t know. Anyhow, I am sure I had to be going 60MPH in places, since the speed limit on that road was 55, and of course truckers would always take it 5 or more over.
 

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As has already been confirmed, it is indeed possible with the right gearing. I can get around 50 mph right now, and that isn't even off of semis. For the most part, I draft buses, large SUV's, and dump trucks and my final gear is a 53x11.

For those reading this, if you try this kind of stuff, try to make sure that you do have an out and that you try to look around the vehicle once in a while to see what is going on up ahead. Drafting trucks, etc. isn't the safest thing to do, and I know I'm an idiot for doing it. I've also scaled back on it. For the most part, I only draft them now until we get up to speed and then I back off right away (i.e., I don't draft them for miles and miles). For me, this is a way to get my sprint training in. What is really scary is hitting a large pothole at 50 mph while doing this. I did just that about 20 years ago. Both tubulars blew out, the rims had v notches in them and were toast, both bottles flew out of the cages, and my face slammed into the stem. How I kept the bike up, I have no idea. That was before the time of cellphones and I had about a 4 mile walk home after that. All in all, it was a happy ending to what could have been a horrible one.
 

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I drafted a couple SUV's today while playing in congested traffic. The safest course for me was tucking in right behind this monster escalade.. I touched 35mph right as I jumped off and I wasn't even trying. As soon as I hit the wind I instantly dropped down to maybe 19? Drafting is fun.. But not exactly smart..
 

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fabsroman said:
As has already been confirmed, it is indeed possible with the right gearing. I can get around 50 mph right now, and that isn't even off of semis. For the most part, I draft buses, large SUV's, and dump trucks and my final gear is a 53x11.
Agree on the stupid, idiotic, incredibly fun part of this. The moronity comes mostly from unseen road surface problems. At these speeds, it takes little to make for a very bad and to the day, especially when you can't anticipate it. What's happening up the road doesn't matter too much - I've found I can stop much faster than they can.

FWIW, buses are the best, followed by motorcoaches. That low back end gives a nice clean pocket. A semi really doesn't clean the air all that well.

I've been to 43 behind busses in dead-flat conditions, and limited only by spinning out my gearing. I won't even begin to pretend I'm a strong rider, either. It's remarkable how easy it is to go fast once the air is out of the calculation.

Aside: The bikes John Howard and his ilk use are fixed-gear, and for an unexpected reason. Once you get to a certain speed (and a carefully-designed shape for the leadout vehicle) the airflow curling back around the windscreen pushes the rider forward, to the exent that they need to apply backpressure to keep from being shoved into the lead vehicle. They use dynamic pressure rather than brakes for obvious heat-related reasons. They also put a special bumper on the vehicle that contacted the bike's head tube rather than the front wheel, to prevent incidental contact from becoming deadly.
 
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