Speaking of cars (and bikes, too!)

[torquer]

This is this week's "Puzzler" from Cartalk, over at NPR:

This was from my continuing series, 'The Adventures of Doug Berman.' Recently our very own Dougie decided to go green and ride his bicycle back and forth to work every day. And the fact that he was just a few bean burritos from that 200-pound mark, may have had something to do with it.

Anyway, Dougie is one of our fair city's few law-abiding cyclists. In fact, he's kind of a fanatic about it. He obeys all the rules of the road. He signals for all of his turns, obeys the speed limits, obeys all the traffic signs and stop lights and even yields to pedestrians. He's a saint!

Well, lately, he has started to record his time for his trips both to and from work and here's the interesting part: When there is moderate traffic on the road, he can make his trip either to or from work a few minutes faster than he can when there is little or no traffic. How could this be? Now he's not hanging onto the bumpers of passing cars or drafting city buses, so what's the story?

http://www.cartalk.com/content/puzzler/transcripts/200943/index.html

There could be a $26 gift certificate in it for you if you come up with the solution. And I think most of us have first-hand experience with the critical element of the answer. ;)

[Keith A]

I think I found the solution in this picture of Dougie riding to work on one of the moderate traffic days...

http://davesbikeblog.squarespace.com/storage/Speed01.jpg

[Sam in VA]

I'd say his bike isn't tripping stop lights. They'll probably add that his frame is carbon.

[Steve in SLO]

I think I found the solution in this picture of Dougie riding to work on one of the moderate traffic days...

http://davesbikeblog.squarespace.com/storage/Speed01.jpg

Hey, that looks just like my gearing...in reverse.

[Tony Edwards]

I'd say his bike isn't tripping stop lights. They'll probably add that his frame is carbon.

The stoplight answer was my first thought as well.

[mister]

i agree on the lights when no cars. probably why they were so strongly stated he's a law abiding rider. he won't run a red ever.

[Nautilus]

I bet he simply rides harder when he's sharing the road, has some more adrenaline going and such.
That's the case for me at least, I love passing cars on my commute.

[palincss]

When do we learn the official answer?

[chuckred]

I'd say his bike isn't tripping stop lights. They'll probably add that his frame is carbon.

Having gotten a ticket before because I didn't trip a stop light...

[Nautilus]

I suppose it depends on where he is, and the route he's taking, but around here I see more red lights as traffic increases.
This is because there are more cars trying cross over, or turn onto the main arteries.

[Keith A]

For me, the biggest influence in my commute times by having more or less cars on the road is the push/draft from the vehicles. Living near the coast in Florida, there is almost always a breeze blowing and typically this is some type crosswind for me. So if there is a good stream a cars going by, not only can this block out the cross/head wind, but you get a push from the cars passing by.

[torquer]

When do we learn the official answer?
Well, if listening to NPR over the weekend is too painfull, they update their website late Monday afternoon.
(Not possitive about the NPR affiliation, but they are on the local NPR station here in NYC.)

[torquer]

And here's the answer:

RAY: Here's the answer. When Dougie leaves for work when there's very little traffic, he comes to a red light and he stops. Because what? He obeys all the rules of the road.

TOM: But of course!

RAY: In fact, Saint Dougie can't even wear a helmet because the halo gets in the way. So there he is sitting there but the light won't turn green for him because many of the intersections in Our Fair City, like other cities around the country, have sensing devices embedded in the road that check for the presence of a vehicle. And because he might not be in the right spot, it stays red forever.

My pal, Jeff Parente, at the Traffic Department told me that these things are not weight sensitive, they work by induction. It looks for a disturbance in the force. And his bike might not be enough to change the light. So he has to wait until a car arrives at the light.

TOM: Ahh.

RAY: And that explains why he doesn't get to the office until two o'clock some days. He's stuck at a red light. So who's our winner?

TOM: The winner this week is Bill McCray from Raleigh, North Carolina. And for having his answer selected at random from among all the correct answers that we got, Bill is going to get a $26 gift certificate to the Shameless Commerce Division at cartalk.com with which he can get our brand-new, just released music CD, Stairway to Heapdom.

RAY: Congratulations, Bill!