View Full Version : Passing Distance

01-30-2007, 06:54 PM
I've recently changed from riding a Univega mountain bike to riding a Bianchi Fremont fixed-wheel during my daily commute to work (through inner southeast to downtown).

I have noticed a huge difference in the distance that cars give me. I used to get a lot of room from cars. Most of them crossed the yellow lines. I never felt crowded. But since riding the Bianchi, cars are passing me way to close for comfort. Today a white van passed by me so closely I could feel it on my face. Most cars now don't bother to cross the yellow lines to give me enough room.

Does anyone else have similar experience?

(It sucks for the cars, though, because I learn to take the lane on certain streets where this happens, so now the cars have to wait longer than if they had just given me more room.)

01-30-2007, 08:18 PM
I am a bit confused... Are you implying the drivers are crowding you because you are on a fixed gear?

I suppose if you were riding in regular clothes, in a very upright position on a mountain bike and now are wearing cycling clothes and on a shiny new bike, the cars may think you are more experienced? Perhaps more confident and thereby able to "deal" with their menacing closeness?

I don't give drivers enough credit to imagine they are paying that much attention. I highly doubt that they are aware of what type of bike you are on, unless they are cyclicts. In which case I hope they give room no matter what brand loyalty they may have!

I have, and have had many different bikes and never notice drivers being any more, or less aggressive. Sadly I rarely have any cross the yellow line to give me room. It is verrry rare for me to see that. I have had countless Rv's, passenger vehicles and semi-trucks nearly clip me while on tours. Visibility as far as you could want, no oncoming traffic and they still won't budge an inch to the left....

If you figure out what was causing them to give you room before, please let us all know! I would love to try it out!

01-30-2007, 09:19 PM
There is a man in England who did a study regarding passing distance. He just published it.

his findings showed that those who wore helmets got less room from motorists than those without. Women also received more room than men. The reason being that motorists feel they can predict behavior with experienced cyclists. if you look like a renob, they'll give you more room.
you're observations have been proven by a person with way too much time on their hands.
So in the grand scheme of things, stop wearing helmets and grow your hair long.

01-30-2007, 09:39 PM
Thanks for the link to that study! I had read a condensed version somewhere that only covered the helmet issue. It was good to see the full article.

It will be interesting to see if she is wearing different clothing, or if she just changed bikes...

01-31-2007, 04:06 PM
Oh man, not that thing again!

I thought we hashed this out before: his study was poorly designed and executed, and didn't include a large or diverse enough study group to get good data.

If he had broadened the scope and had an outside observer measuring somehow, or if there was some way to take the "human aspect" out of it (i.e. maybe this driver was having an exceptionally good day and felt like giving room; maybe that driver was pissed and feeling belligerent and didn't feel like giving room; maybe this other driver was distracted by cell phone or radio or screaming kid in back seat and ordinarily would have given room; you get my point, yes?) the study may have been worth more than the paper it's printed on. Or the bits representing it on the internet. :)

I'm sorry, I just don't think this is a good study, certainly one I'd point to, to justify the way people drive or the lack of room they give me. I'm female, by the way, and haven't noticed people giving me extra room.

Now, if he had done it from the other side of the windshield; maybe have X number of cars installed with proximity sensors and a brave cyclists to ride along a stretch of road, back and forth.... I don't know. I'm not a scientist.

norse rider
01-31-2007, 05:48 PM
Commuting four to five days a week I notice that during daylight hours the passing room given to me is tight. I had a car brush by me yesterday morning with no more then five inches to spare. At night however I get quite abit more room. This could be due to the four tail lights I run and the three headlights but who knows. As my neighbor says I am lit up like a X-mas tree.
Some days are great for passing room and others just flat suck.

01-31-2007, 10:01 PM
The study inclued 2500 passing motorists. the study was performed on the cars (including their drivers habits), not on the cyclists. the control was him riding w/ helmet, the experiment was w/out a helmet. he used a laser sight to find the distance to the cars.
Driver behavior was the whole point of the study, so cell phones and french fries are included with the driving habits, the one that was studied was passing allowance. His results were statistically significant, 8.5 cm more without helmets.

02-01-2007, 01:20 AM
uh, 8 and a half centimeters? what is that? like a mind-blowing 3 inches? wow.

02-01-2007, 01:21 AM
i'll keep my helmet on, thanks.

02-01-2007, 09:18 AM
How about this: http://www.stc-law.com/mimicry.html Again, not a comprehensive study, but some good personal experience that seems to indicate that you can gain some respect on the road based on appearance. With all the highly publicised "backlash against cyclists", it may be that riders who are instinctively identified primarily as "cyclists" are getting less respect than those who are seen as some other type of ordinary person who just happens to be on a bicycle. In my opinion, this is the underlying attitude at work in the british study (which is valid, but not nearly as comprehensive as it needs to be in order to truly be useful - I hope they're not done); the drivers give more room to an apparently female rider with long hair not because they feel such a rider to be less experienced or more unpredictable, but because they think they have spotted a babe, and no one wants to run over a babe - spoils your chances, eh? I myself tend to get a lot of room on the road, and I attribute this largely to the cargo bike I ride, and my somewhat distinctive (not to say outlandish) appearance. Stay safe, all.

02-04-2007, 03:49 PM
I am sorry I didn't word my post more clearly. I haven't changed clothes or routes or times. I, too, highly doubt that cars notice whether I am on a fixed wheel or geared bike. The difference would mostly be my position whether I am on a mountain frame or a road/track frame. I think that position is maybe what gives them cues to give me more or less room. However, it could simply be random chance, or an increased sensitivity due to being less comfortable on an unfamiliar bike.

I have read Walker's study, and in my opinion as a scientist-in-training (in biology), there is nothing wrong with the design of the study. The issue seems to be the interpretation that some people are taking from it. I do think there's something to think about, because the decrease in passing room that I perceive has made an impact on how safe I feel on the road. I don't think the few inches you gain from not wearing a helmet make up for the increased amount of damage you get from not wearing one if you were to be in an accident.

I just thought it would be interesting to see if anyone else noticed a difference in passing distance based on what bike they rode (assuming all other variables the same).