Dave Moulton

Dave's Bike Blog

Award Winning Site

More pictures of my past work can be viewed in the Photo Gallery on the Owner's Registry. A link is in the navigation bar at the top

Bicycle Accident Lawyer






Powered by Squarespace
Search Dave's Bike Blog


 Watch Dave's hilarious Ass Song Video.

Or click here to go direct to YouTube.


A small donation or a purchase from the online store, (See above.) will help towards the upkeep of my blog and registry. No donation is too small.

Thank you.

Join the Registry

If you own a frame or bike built by Dave Moulton, email details to list it on the registry website at www.davemoultonregistry.com

Email (Contact Dave.)

 If you ask me a question in the comments section of old outdated article, you may not get an answer. Unless the article is current I may not even see it. Email me instead. Thanks Dave

« Opting out of the system | Main | Designing Bikes for Women »

Please, just go around me


More and more states are bringing in “Safe Passing” laws to protect cyclists. As they do, more and more motorists complain that they cannot safely pass cyclists on winding country roads without crossing the double yellow line and putting themselves and others in danger.

I contend that drivers are making more out of this issue than there really is. First of all, yes you have to cross the double yellow that is obvious. However, realize that it is a painted line, not a concrete barrier, you can easily drive over it and back again.

Second, get the issue in perspective; it is not like passing an eighteen-wheel semi. A bicycle is less than six feet long, and barely eighteen inches wide. A cyclist needs about a third of the lane width, maybe half, depending on the overall width of the road.

It is nice when drivers go completely over to the other lane to pass, but it is not always possible, and often it is not necessary. Just straddling the yellow line in most cases gives a cyclist enough room; a lot depends on speed.

If I am doing 20mph and a car passes me at 30 mph, it doesn’t bother me too much if I am passed at slightly less than 3 feet. However, pass me at 60 mph and I would prefer a lot more room. A common sense rule would be, 3 foot at 30 mph, and one more foot per 10 mph over that.

The main problem is that many motorists view overtaking a cyclist in the same light as overtaking another car. Any sane person would not usually overtake another car if there is opposing traffic, say 200 yards away. 

However, the fact that a cyclist is moving at a relatively low speed is actually to your advantage when overtaking. You can safely pass a cyclist with approaching vehicles within 200 yards, even if you have to exhilarate from 20 mph.

Just do the maths. One mile per hour equals 1.467 feet per second traveled. A cyclist doing 20 mph would travel 29 feet in 1 second. (20 x 1.467 = 29.34 ft.) A car passing the cyclist at 30 mph would travel 44 feet in 1 second. (30 x 1.467 = 44.01 ft.)

Double this to 2 seconds for the sake of safety, that’s “One Mississippi, two Mississippi” and you are safely past the cyclist and on your merry way, back on your own side of the road.

Now let’s say there is a car approaching at 60 mph; your combined speeds are 60 + 30 = 90 mph. This equals 132 feet per second. (90 x 1.467 = 132.03 ft.) So 2 seconds translates to 264.06 feet, or 88.02 yards.

So if you overtake a cyclist with an approaching car 100 yards away you may be cutting it close, but 200 yards and you have doubled you margin of safety.

Plus, don’t forget you already doubled the time to pass the cyclist to 2 seconds. Also remember, you are not fully in the opposing lane, and not for the full 2 seconds.

The problem is, you get one timid driver who will not pass a cyclist if there is opposing traffic anywhere within the same zip code.

Traffic gets backed up, and everyone is pissed off. And who gets blamed? Why the cyclist of course, when it is not he that is holding everyone up, but the pussy of a driver afraid to overtake.

So please motorists, the next time you see me out on the road, just go around me and stop making such a big fuss.


 To Share click "Share Article" below

Reader Comments (11)

Perhaps that simple math should be included on all license-to-drive tests.

Or which is easier to pas? A large SUV, cyclist or semi?

January 15, 2015 | Unregistered CommenterJack


Interesting. When I started out cycling years ago, veteran riders gave me several bits of advice:
- Ride about 2-3 feet off the line until a car approaches; as it goes to pass you, move a foot to the right to open a bigger gap.
- As you ride and hear a fast car or pickup truck approaching, make a little swerve out and back in. You show the driver some lateral movement that signals them to be aware you may change your line. A quick flick of the front wheel is enough to show them a bit of unpredictability.
- Try to turn your head and show eye contact with the driver over your shoulder. People react completely differently when there is a meeting of the eyes than when they're rolling up on an anonymous backside.
Curious if you or your readers endorse/condemn any of these tricks, and if hey have any of their own.
I've also seen some studies that show a flashing rear light, even in the daytime, seems to influence drivers.

January 15, 2015 | Unregistered CommenterEd

Since I started using my rechargeable lights
I have had more motorists tell me, "Those lights are great." I was stopped one time, taking a break, when a car driver pulled along side me to tell me he could see my flashing rear light from half a mile away. In fact he mentioned he thought it was a cop car. What better way to get a driver's attention that to have them think a cop or other emergency vehicle is ahead.
And yes, if I am about to change lanes, or even take the lane for some reason, I turn my head as well as give a hand signal. Turning your head to look behind is a universal signal that you are about to do something. Whereas a hand signal alone can go un-noticed or ignored.

January 16, 2015 | Registered CommenterDave Moulton

Being passed is (yet) another reason to have a good mirror affixed to your helmet. I live in a town populated by elderly drivers and walkers. This demographic fits many communities in the United States and most of the State of Florida. The mirror has saved me more times than I care to admit from a wandering, usually ancient driver who decided that driving in the bike lane is perfectly acceptable as they toddle happily along at 25 mph in a 45 mile zone.

California passed a 3 feet law last July and people moved over and made plenty of room for bicycles. As time passed, however, the margins became narrower, but not unacceptable. The San Francisco Bay Area has a lot of bicycle riders and drivers are used to seeing us. The result is that MOST people give us plenty of room.

Coming down our wonderful mountain passes, however, we (bicyclists) frequently end up passing cars, likewise in the heavy traffic that infects our neighborhoods during commute hours. There's nothing quite so fine as wondering whether you need to give automobiles the same three feet of clearance. Tit for tat (as it were).

January 16, 2015 | Unregistered CommenterJames Thurber

I am intrigued by your comment about the benefits of a mirror. I have never used one when cycling, partly because I've always been skeptical that there would be enough time to react to whatever danger that came into view. How did you actually avoid the wandering menace from the rear? However, I am open to persuasion on this one and would welcome a response.
Regarding the 3 Feet law, I have mixed feelings. In my opinion, the most dangerous motorists are those that want you to know that they are there, in other words those that buzz you to show you who's boss. These types are not affected by the 3 Feet Law because they ignore it.
In conclusion, we cyclists must all do a certain amount of risk assessment, and we get out there because we like our chances overall.

January 17, 2015 | Unregistered CommenterMartin W

I MUST respond to Martin's post about mirrors. Since I've been back to riding (about the past ten years or so) I've become a card-carrying, no-nonsense pro-mirror partisan, and I am convinced that my mirrors have saved my life at least twice. I wrote about it in my blog post.


Finding a mirror that worked for me was almost as frustrating as finding a saddle I like (although it was substantially less expensive). I've changed mirrors since that post, and I'm not going to link to the ones I use (but I will say they have wire, not plastic, helmet connectors), and I also keep one on the bike because I don't always ride with a helmet (Sssh - it'll be our little secret, OK?).

January 20, 2015 | Unregistered CommenterPlain Jim Brittain

I began using a mirror when it became painful to twist my head around to see what that noise was coming up behind me. Fortunately in the "Land of Electric Cars" (San Francisco Bay Area) tires make plenty of noise.

The mirror gives me, in an instant (instant!), a clear view of what's behind me. Most of the drivers that drive in our bicycle lanes are really old (and fortunately quite slow) - just like me.

There's plenty of time to get out of the way, weave (making yourself more visible), or bail to the right (left in New Zealand, Australia and Great Britain).

Besides, if I forget to put on my helmet (another age issue) the instant I try and view behind me I realize my mirror / helmet are still at home, ergo: turn around!

What's now becoming an issue in our wealth infused region (Los Altos / Palo Alto / Mountain View) is that people have begun treating traffic signals as being "not applicable to them." Blatant red light runners are everywhere, drivers making U-turns across double yellow lines to snag a parking place, stop signs not applicable to them, etc. When queried they respond, "Heck, I've got so much money a ticket doesn't matter to me."

I just hope they have lots of insurance.

January 20, 2015 | Unregistered CommenterJames Thurber

Everything Dave says make perfect sense to me as a rider - 'just pass me' - it's not that hard. But I'm convinced that some drivers have great difficulty jusdging the relative speeds of 2 moving oblects (or 3 if there's an oncoming vehicle),, and hence make a bigger deal out of passing a biker than they should. Are Americans worse than Europeans at this, women worse than men, do we lack training, or are we as a society somehow losing our spatial acuitty? Not for me to say, but we need lots of work on this.

January 20, 2015 | Unregistered CommenterVJ

Bad driving has nothing to do with gender, intelligence, culture or ethnic origin.

The worst drivers are those unfortunate bicycle riders who, because of sinful behavior or simply bad luck, are forced into driving one of those polluting, vicious, murderous vehicles (aka: an automobile).

The human brain is designed to function at a top speed of approximately 20 mph - the speed at which most humans can run - and no more then that. Whenever I've been forced into driving a car and find myself behind a bicyclist I simply slow down to the speed of the bicycle. I'm much more comfortable at that speed. Life is good and, if it's my wife's car, the seat is adequate (it even reclines, yawn, ZZzzzz).

Unfortunately my fellow vehicles do not see eye to eye with me on this following bicycle / speed issue. I get a lot of horn honking, vicious looks and the occasional middle finger wave.

But look at how high speed highways are designed and note how everything has been spread out to the point where our 15 / 20 mph brains can absorb what's happening.

January 20, 2015 | Unregistered CommenterJames Thurber

Its FATE that all it is! The so called, 'luck of the draw'. Has nothing to do with saftey or what ever precautions you take, UNTILL this country starts adopting rules that put away for life, the crimnals that are driving motor vehicles DRUNK nothing will change.Colorado just passed a law sayig that on the THIRD BLOODY DUI the drived will be filed with a felony. THIRD DUI?? HOW ABOUT THE FIRST ONE? "Oh I think I have had to much to drink but I THINK I can make it home OK" A couple of months ago a CYCLIST was KILLED by a CHURCH BISHOP she had been charged BEFORE with DUI SHE WAS A BISHOP!!!!! The church knew about this, BUT she WAS drunk, left a bar killed a cyclist, then left the sceen of the accident, but when she relised her windshied was broked, she figured she had better see what she hit. HOW MANY MOTORIST RIGHT are driving vehicles DRUNK or STONED? Maybe, JUST maybe IF the drivers KNEW, they would go STRIGHT to jail and loose their lic for a year or two MAYBE and this IS A MAYBE they would think twice about driving. So you ride your bike on the roads you take YOUR chances, THATS ALL IT AMOUNTS TO, GOOD LUCK! Sad BUT true

January 20, 2015 | Unregistered Commenterjohn crump

Maine's "give room to cyclists" law specifically allows overtaking drivers to cross the centerline to do so (providing there is no oncoming traffic, of course.)

March 14, 2015 | Unregistered CommenterSteveP
Comments for this entry have been disabled. Additional comments may not be added to this entry at this time.