Engineering Knowledge, Planning Superstition

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The bikeway controversy started in 1937, when the British Cyclists' Touring Club fought off their government's attempt to put cyclists on sidepaths, paths running alongside the roadway in the manner of sidewalks. The CTC fought this off by citing the dangers of the sidepath system. Bikeways were ignored in the USA until about 1970, when motorists became concerned that the "bicycle boom" would cause roads to be jammed with bicycles. California then contracted with motor-traffic consultants to design bikeways, set up a committee to produce traffic laws requiring cyclists to use bikeways, and set out to build bikeways wherever motorists wanted them.

I discovered this activity, and alerted California cyclists into opposing this proposed bikeway system. It was an intense fracas. While the obvious function of the bikeway designs was to make motoring easier by pushing aside bicycle traffic, those opposed to motoring joined the motorists' side of the dispute. They argued that pushing aside the bicycle traffic made cycling so safe that many motorists would switch from motoring to bicycle transportation.

California cyclists managed to get the most dangerous bikeway designs rejected, and to prevent the most dangerous traffic laws. With government thus protected against the worst liabilities from very dangerous designs, these bikeway designs became the national standard, and government has a program of paying local authorities to employ bicycle planners to build them. However, these designs were never intended to either reduce car-bike collisions or to make safe cycling easier. The design committee never considered designing with these purposes. All that the cyclist critics managed to do was to reduce the amount of added danger produced by these designs.

The adoption of these standards, which agreed so completely with what the public thought it knew about bicycle riding, prevented public and scientific discussion of the subject for twenty-five years. For example, the Bicycling Committee of the Transportation Research Board, an arm of the National Academy of Sciences (to which I belonged and for which I refereed papers), ought to be the nation's most prestigious scientific body regarding bicycle traffic. However, that committee accepted many papers praising the bikeway system and its associated theory of incompetent cycling, papers that had no scientific justification, while rejecting papers that criticized the bikeway system for solidly scientific reasons. The other referees managed to do these things by continuously violating the standard Rules for Referees by Bernard K. Forscher, published in Science.

The government paid bicycle planners to produce documents justifying the bikeway system. One of the most notorious of these papers is Selecting Roadway Design Treatments to Accommodate Bicycles, a Federal Highways Administration Manual. This stated that since 95 percent of bicycle riders will always be incompetent, the bikeway system is necessary to accommodate these incompetent people. This argument dodges the critical issue: bikeways were never designed to reduce the level of required skill, and nobody has ever demonstrated which items of cycling skill are no longer required with a bikeway system. Another equally notorious paper is Bicycle-Safety-Related Research Synthesis: FHWA-RD-94-062. These papers were co-authored by Andy Clarke, now employed by League management as their Executive Director.

Similarly, the planning profession, which, by and large, is opposed to motor traffic in cities, published numerous papers about wonderful bikeway systems, without ever a hint of criticism; proposed papers criticizing bikeway thought were rejected. The underlying reason for rejection was that cycling on normal roadways was an improper policy because it was an elitist activity that required extreme levels of skill, courage, and physical power.

One of most prolific bike-planning authors is Professor John Pucher of Rutgers University. He produced a series of papers, one of which appeared in Transportation Quarterly, presenting the standard bikeway advocacy. In email discussion of these papers, Pucher exploded with the comment that I was totally wrong and an elitist because there were no facts at all on my side of the argument. That explosion in recorded discussion gave me the opportunity that I had sought for decades. I communicated the substance of the discussion to the editors of Transportation Quarterly, with the statement that I was prepared to present the well-established and long-known facts and reasoning in bicycle transportation engineering that were apparently unknown to Professor Pucher. Given that challenge to a direct claim by their author, the editors could hardly object.

The result was the article copied below, on the subject of The Bikeway Controversy. Of course, it is up to you, the reader, to assess the accuracy of my facts and the validity of my reasoning. But notice that most of the material was officially published many years ago; very little is new, and this is mostly new discussions of old facts. This is the level of information that has always been available to planning professionals, and has always been particularly pertinent to bicycle planners. And yet, they manage to pretend ignorance, and get away with that pretense, because the only opposition comes from lawful, competent cyclists, a group whom our society considers to be nastily elitist and untrustworthy. I repeat, it was only Professor Pucher's direct statement that there were no facts on the vehicular cycling side that enabled me to get this paper into the professional transportation press, and it is the only paper presenting a reasonable view of transportational cycling that has appeared in the professional transportation press. (There have been several papers presented to traffic engineering conferences and the like, but they don't get beyond the conference anthology. One of the best is Paul Schimek's The Dilemmas of Bicycle Planning, presented to The Joint International Congress of Schools of  Planning, Toronto, 1996. Despite many references to it in discussions by cyclists, it has not appeared, or been seriously discussed, in the professional journals. It is available at: )

The Bikeway Controversy

This article appeared in Transportation Quarterly, Spring 2001, Vol 55 No 2. 
Copyright John Forester

The Controversy

For twenty years in the U. S. there has been a great controversy about bicycle transportation, which grew out of controversies in Europe going back to the 1930s. (Oakley 1977; pp 29, 51, 53, 85-86, 129-130. Forester 1994; Chap 4, Governmental Actions, Chap 13, Bikeway Controversy) On one side are the lawful, competent cyclists, who say that "cyclists fare best when they act and are treated as drivers of vehicles," which is the basic principle of the traffic laws, and which is called the vehicular-cycling principle. On the other side are the bikeway advocates, who say that cyclists should ride on bikeways, preferably bike paths in the Dutch manner, without specifying how this should be done. Bikeway advocates oppose cycling on the road in accordance with the rules of the road by arguing that it requires mental skill, physical power, and psychic temperament close to the limits of human abilities. Among bikeway advocates are both militant motorists, who want to clear the roadways of cyclists, and militant anti-motorists, transportation reformers, and urban planners, who believe that providing bikeways will cause many motorists to switch to bicycle transportation in the belief that the bikeways will have made cycling safe. This odd mix of concepts I call the bikeway superstition.

Classic Bikeway Argument

I start by discussing the bikeway argument because that is the side that is most familiar to most readers and is one which they probably trust the most, if only because its familiarity has made it seem undoubtable. Only after the weaknesses of the bikeway argument are disclosed, will the reader be willing to consider the merits of the vehicular-cycling principle.

The classic argument for bikeways, presented many times, is that the Netherlands has the best-developed bikeway system in the world, and it also has a very large proportion of urban bicycle traffic with a low accident rate. Bikeway advocates argue that the bikeways caused both of these results, without further discussion, although they sometimes add other factors, such as selected aspects of Dutch traffic law that favor cyclists (while ignoring those that disfavor cyclists). The latest prominent expressions are Pucher 1999 and Pucher 2000.

Analysis of the Classic Bikeway Argument

Correlation Does Not Demonstrate Causation

The bikeway advocates' argument is purely one of correlation. Its weakness is that correlation does not demonstrate causation. While the argument does not demonstrate causation, it does demonstrate something else. The fact that this argument is made so strongly demonstrates the strength of the belief that it must be true, even without supporting evidence.

The Popularity Argument

The advocates' argument has two aspects: bikeways persuade people to take up bicycle transportation, because bikeways make cycling safe. There is plenty of evidence that the general public believes that bikeways make cycling safe. There have been many surveys showing that people say that they are most inhibited from cycling by the dangers of traffic and that if they had bikeways they would be much more likely to cycle for transportation. Bike planners typically try to calculate the number of transportational cyclists who will use a proposed bikeway, and many of the FHWA's National Bicycling and Walking Studies were devoted to this concept. However, I know of no transportational bikeway system which has met those projections.

As the FHWA phrases it: "Nearly 100 million peple in the United States own bicycles. ... fewer than 5 percent would qualify as experienced or highly skilled bicyclists ... [the 95%] are casual or new adult and teenage riders who are less confident of their ability to operate in traffic without special provisions for bicycles. ... They prefer ... well defined separation of bicycles and motor vehicles on .. bike lanes or shoulders or on separate bike paths." (FHWA 1992)

In any argument from correlation, the causal linkage may run either way. For example, the presence of many cyclists, as in many college towns, provides the political incentive to provide bikeways, rather than the bikeways attracting the cyclists who would have been there in any case. Indeed, the initial motivation for the much-praised Davis bikeway system was the intent of the city's residents to prevent the student cyclists of the projected university from blocking the residents' motor traffic. (Forester, 1994, pp 24, 88, 158)

The Safety Argument

The popularity argument ultimately rests on the assumption that bikeways make cycling much safer, particularly for beginners, those who do not know how to obey the rules of the road for drivers of vehicles. The argument from correlation is clearly insufficient here, because there are so many other factors that might contribute to the accident rate. However, I know of no instance in which a bikeway advocate has analyzed accidents to cyclists to see by how much, and by what mechanism, bikeways could reduce the accident rate. Note that the quotation from the FHWA Manual (above) indicates that the Federal Government has given up on the safety argument and now relies on the preferences of those who are most ignorant of the subject. Despite thirty years of attempts by governmental bikeway advocates (California 1972, FHWA 1975-6, FHWA 1994), nobody has been able to demonstrate either of the two critical theories. The first is that urban sidepath systems provide either safer cycling at the same speed, or faster cycling at the same accident rate, than does cycling properly on the roadway. The second is that painting bike-lane stripes (the only feature that distinguishes bike lanes from wide curb lanes) either reduces the accident rate for competent cyclists, or allows cyclists of lower skills to cycle at the same accident rate.

It has fallen to the bikeway opponents, the vehicular cyclists, to state the bikeway argument that the bikeway advocates shy away from stating. Here it is. Same-direction motor traffic is the greatest danger to cyclists. Bikeways separate cyclists from same-direction motor traffic. (Clearly, bikeways don't separate cyclists from crossing or turning motor traffic, and there is little danger from opposite-direction motor traffic.) Therefore, bikeways make cycling much safer by eliminating the danger of same-direction motor traffic.

Consider what is stated to be the greatest danger to cyclists. Table 1 shows he general causes of accidents to cyclists.


Type of Accident




Car-bike collision


Bike-bike collision


Bike-dog collision


All others


Now consider the types of car-bike collision in Table 2: The specification of urban traffic is made because transportational bikeway systems are proposed only for urban areas, and the accident pattern on rural highways is different. These tables are taken from the chapter on accidents in Forester, Effective Cycling, Greater detail is available in Forester, Bicycle Transportation. The data are taken from Cross & Fisher, Chlapecka et al., Schupack et al, Kaplan, and both the data and the analyses have been available since 1977.


Type of car-bike collision

Prop. in urban traffic

Turning and crossing


Motorist overtaking cyclist


Other parallel paths


In short, what bikeway advocates term the greatest danger to cyclists, the motive for bikeways, is, at most, 7% of 17%, or 1.2% of accidents to cyclists. Even if that cause were entirely eliminated, the change would not make cycling sufficiently safer to justify the bikeway program.

The Fatal Accident Argument

Because the general accident argument does not support the bikeway argument, bikeway advocates have started to rely on the fatal accident argument with modern statistics. (Geary 2000) With the decline of child cycling in the U. S., child casualties are a smaller proportion of the total. Fatal accidents are only about 0.2% of accidents to cyclists, and only about 1% of car-bike collisions involving injury or death. Because of the physics of collisions, higher motorist speeds greatly increase the probability of fatal injuries. High motorist speeds are typically found on roads with few intersections and driveways, and few of the conflicting movements that these create. Therefore, cyclist fatalities are concentrated on high-speed roads, and, therefore, are disproportionally of the motorist-overtaking-cyclist type. This proportion does not demonstrate that these conditions are highly dangerous; it may only demonstrate that the causal factors for the other types of collision are not present. However, there is some evidence for an increased incidence per bike-mile, which is a better measure of danger.

Nighttime fatal car-bike collisions are also overrepresented in the statistics, but the cause is uncertain. A greater proportion of cycling on high-speed roads as a consequence of the absence of child cyclists who normally use slow-speed roads; higher nighttime motoring speeds in general (motorists have higher fatality proportions at night, also); the deliberately dim design of bicycle rear reflectors specified by the U. S. government; the general failure to use bicycle headlamps; part of the alcohol abuse problem: all these have been advanced. Forester's analysis of nighttime car-bike collisions (Forester, 1994, p67) shows that 3/4 of them are of the type in which the absence of a headlamp would be an important causal factor, while for only 1/4 of them would defective rear conspicuity be a causal factor, but, as in daylight collisions, those from the rear have a disproportional amount of fatalities.

For these reasons, emphasizing fatal accidents occuring as motorists overtake cyclists makes a useful argument for bikeway advocates, because motorist-overtaking-cyclist collisions are the only type of accident that bikeways could reasonably be considered to reduce.

Substantial questions remain: how many more injury accidents are worth one fewer fatal accident; would bikeways be built where most effective in achieving even this result?

The Vehicular-Cycling

Even assuming that bikeways eliminated all car-bike collisions caused by motorists overtaking lawful cyclists, that does not mean that the accident rate would be reduced, or that cycling would be made better; one has to consider the dangers and discriminations that bikeway systems create.

Dutch Bikeway Dangers

Any ubiquitous urban bikeway system has to run largely along the existing streets, because these are the only spaces generally available. Practically all urban bikeways put the cyclist to the outside of the motor traffic, in a bike lane or sidepath. Consider a cyclist traveling straight along the much-praised Dutch sidepath system. Every driveway becomes an intersection. At every normal intersection, motorists from his right fail to yield to him, but cross his path to yield to the motor traffic on the roadway. Motorists from his left are only too glad to cross the roadway when the roadway is clear, and don't look to yield to him coming fast along the path. At every normal intersection, the straight-through cyclist is at the right of right-turning motor vehicles, whose drivers don't see him until the moment of collision. Motorists from the opposite direction who turn left across his path see and yield to traffic on the roadway, but rarely to traffic coming fast along the path. If the cyclist wants to turn left, he must make his left turn from far to the right of all the motor traffic, turning across those lanes of same-direction motor traffic while having to look ahead for the crossing and opposing-direction motor traffic. This is a situation that is beyond any, let alone just normal, human capability, because we don't have eyes in the backs of our heads and the brain system to comprehend all-around vision.

Diagrams illustrating these problems and analyzing the human factors involved have been available since before 1977, and are given in Forester, 1994, chapter 9, The Effect of Bikeways on Traffic.

Traffic Law for Sidepaths

Cycling on a sidepath, relative to motor-vehicle traffic, is the same as cycling on a sidewalk. Because of the problems described above, the Uniform Vehicle Code 11-1210(c) has since 1975 required that "A person propelling a vehicle by human power upon and along a sidewalk, or across a roadway upon and along a crosswalk, shall have the rights and duties applicable to a pedestrian under the same circumstances." UVC 11-502(b) states: "No pedestrian shall suddenly leave a curb or other place of safety and walk or run into the path of a vehicle which is approaching so close as to constitute an immediate hazard."

Considering the placements of cyclists and motorists in a sidepath system, it is difficult to see what other law would be effective. In other words, to avoid becoming the victims of car-bike collisions, cyclists using sidepath systems must proceed with the low speed and greater delays of pedestrians, instead of the higher speed and smaller delays of drivers of vehicles.

The Evidence of Bikeway Standards

The first U.S. attempt at bikeway design standards was California's copy of Dutch designs (California 1972). That was retracted before issue as being far too dangerous. The second was the Federal government's combined design standards and supporting research report (FHWA 1975). That was never adopted because the research was demonstrated to be defective. The third attempt started in California (California 1976), and was then adopted by the Association of American State Highway and Transportation Officials and the Federal government as the AASHTO Guide (AASHTO 1981).

Forester was a major actor in all of these events, and he points out that the present bikeway standards were never designed to reduce accidents to cyclists. That subject was rigidly excluded by the majority of the design committee. The only consideration was how to clear cyclists from the "motor traffic" lanes without endangering cyclists to the extent that government would become liable for personal injury suits. (Forester, 1994, chap 4; 1993, chap 46) Therefore, any reduction of accidents to cyclists that may appear in conjunction with the installation of bikeways is purely fortuitous and probably the result of accompanying actions rather than the bikeways themselves.

Empirical Evidence

Actual Sidepath Test

I know of only one valid test of a sidepath system, my own. Palo Alto instituted its mandatory sidepath system along my route to work, which I had used for several years with no problems and no incipient collisions. After I had been convicted of continuing to ride on the roadway, I was hounded by bikeway advocates saying that this system had been instituted for the safety of cyclists and that my ill opinion of it was unfounded. Therefore, I decided to ride that system using the same speeds and right-of-way that I had enjoyed on the roadway. After all, if the system was safer, then it would be safer at the same speeds as before. Seven times in five miles I faced incipient car-bike collisions that I was able to avoid only by the combination of expert understanding of traffic with expert bicycle handling skill. Few other cyclists would have avoided any one of these. The cyclist who had observed part of the test was white-faced and incapable of speech when she met me at the end. I tried once more, and in my atttempt to make a left turn the only course I could take that would not certainly involve me in a car-bike collision was to ride head-on in the reverse direction into an oncoming two-lane platoon of cars, riding the lane line and hoping that no motorists was in the process of changing lanes. I terminated the test because of its excessive dangers.

Since I had had no such incipient collisions in several hundred days of use of those roadways, and had seven in the first attempt to use the sidepaths, I concluded that the risk rate was at least 1,000 times greater on the sidepath than on the roadway. This test has been reported in all the various editions of Effective Cycling and Bicycle Transportation.

Bikeway advocates deride this test: "infamous ... simply ignored by non-vc types as a biased and unscientific anecdote against sidepaths that has little relevance to the real world as they see it." (Geary, Riley; public e-mail comments on the draft of this paper.)

How is this test biased and unscientific?

As to method, I rode the sidepath at the same speed and with the same expectation of right-of-way that I had used on the road. I could not overstate the severity of the test, because I was physically incapable of riding much faster; I could not be given greater right-of-way than I had on the roadway.

As to evaluation? When I wrote that it took both unusual traffic comprehension and unusual bicycle handling skills to avoid the eight incipient car-bike collisions, was I overstating the case? Considering that bikeway advocates complain that I have excessive skill, and that I terminated the test after so short a period, that speaks for the dangers of that test for the ordinary cyclist.

As to replicability? One test, properly done, is valid scientific evidence, but repeated tests are better. In this case, there has been only one test. You cannot arbitrarily throw out the data from the only test that exists because you don't like the results. The logical people to repeat this test are not people like me who won't repeat it because we won't risk our lives in what we believe to be an extremely dangerous test, but those who believe that urban sidepaths make cycling safe for beginners. They are the ones objecting to the results of the test, and none of them has tried repeating that test. They can't plead ignorance of my test, for it is "infamous" in their circles.

Bikeway advocates see no point in trying to replicate the test because they object that it is of "little relevance to the real world as they see it." That is, they see no purpose to be served by bicycling faster; they openly denigrate the desire to reach one's destination in less time. Of course, they do not mean this. If they did, they would walk rather than cycle. Their argument means that it is acceptable to want to go as fast as their slow facilities permit, but unacceptable to want to go as fast as cyclists can safely travel on the roadway.

One might consider this absurd. It is. The bikeway advocates are so imbued with the imagined virtues of the Dutch bikeway system, that it makes cycling safe for the incompetent and creates many cyclists where there were few before, that they have transformed, in their own minds, the defects of the Dutch system, its slow speed and long delays, into virtues.

Sidepath Statistical Evidence

For whatever reasons, Palo Alto then repealed their mandatory sidepath law. In 1994, Wachtel, Lewiston and Likens showed that even at low cycling speeds the bikeways that I had tested in 1975 produced a car-bike collision rate 1.8 times that for the adjacent roadways.

In 1998 William Moritz showed that sidewalk cycling (which present the same motor-traffic hazards as Dutch sidepaths) have an accident rate 25 times that of major roads without bicycle facilities. (Moritz 1998)

Although sidepaths are only one class of bike paths, in 1976, Kaplan (p 75) showed that, for club and transportational cyclists, the accident rate on bike paths was 2.6 times greater per bike-mile than their average on roads.

General Car-Bike Collision Statistical Evidence

There are two types of bicycle accident statistics available. Studies of populations of cyclists give general accident rates for these populations, classified into major classes of accident, while studies of car-bike collisions give detailed information about the various types of car-bike collision but not much information about the types of cyclist involved.

The best source of statistics about car-bike collisions is Cross 1976. Hunter et al's 1996 study did not improve on the few difficulties recognized in Cross's typology, and the data analysis method is inferior. Table 3 is my analysis of Cross's data for urban areas, for all types over 2%.

Rank Order of Urban Car-bike Collision Subtypes

Type #






Cyclist proper side of road runs stop sign





Motorist turning left hits cyclist head-on





Motorist restarting from stop sign hits wrong-way cyclist





Cyclist turns left in front of overtaking car





Cyclist hit on light change





Motorist turns right





Cyclist exits residential driveway





Motorist restarts from stop sign





Cyclist exits commercial driveway





Cyclist on sidewalk turns to exit driveway





Wrong-way cyclist runs stop sign





Wrong-way cyclist hit head-on





Motorist exits commercial driveway, hits cyclist on sidewalk





Uncontrolled intersection collision





Motorist exits commercial driveway





Cyclist runs red light




c=correct road position

s=sidewalk riding

w=wrong side of road

t=cyclist swerve




Some argue that the decreased proportion of juvenile cycling in the American population since 1975 should decrease the significance of the accidents incurred by juvenile cyclists. However, bikeways are specifically intended to provide for the child and beginning cyclist, and are predicted to create a resurgence of cycling in the population. If that is so, then the importance of the accident types for child and beginning cyclists should be magnified, not reduced.

As you can see, very few of the car-bike collisions would be prevented or ameliorated by bikeways, while the movements of many would either have to be performed under more difficult conditions or the conditions that caused the accident would occur more frequently with bikeways. It is more likely that the general introduction of bikeways into the American traffic system would increase car-bike collisions than reduce them.

Evidence of the Effect of Skill

The classification by age groups in Table 3 shows that cyclists learn by experience. The easy-to-avoid types fall off fast after the childhood years, those that require some understanding of traffic operation fall of after the teen-age years, while those that are hard-to-avoid, even impossible for the cyclist to avoid, continue into later life.

There is more definitive evidence of the effect of skill in reducing accidents and car-bike collisions. The American studies of school-age cyclists and of college-associated cyclists (Chlapecka 1975, Schupack 1976), and of club and regular commuting cyclists (Kaplan 1976) give accident rates per bike-mile. The accident rate of club and regular commuting cyclists is about 20% to 25% (depending on the type of accident) of the accident rates of the general bicycle riding public. The study of British club cyclists (Watkins 1984) provides accident rates for cyclists of different durations of experience. This again shows that four years of club cycling experience reduces the accident rate to 25% of that for those who entered from the general cycling public.

Cross's data above the youngest ages show few instances where the car-bike collision was caused by lack of control by the cyclist. The reduction in car-bike collisions with experience is caused by better understanding of traffic behavior, as will be discussed in the next sections.

The Evidence from Cyclist Behavior

Forester (1978) measured the traffic behavior of four groups of cyclists: the cycling populations of three university cities: Davis, Berkeley, and Palo Alto; and a group of mature club cyclists riding in Palo Alto and nearby cities. The standard was the vehicular-cycling standard described in Effective Cycling. Forester compared the proportions that did not meet that standard for the actual mix of types of traffic movement that were made by the cyclists of each area. Forester made sufficient observations to attain 95% confidence in 7differences and 99% confidence in 15 differences. Some differences reflected the difference in design between the two bikeway systems (Davis and Palo Alto), others reflected both that and the general difference in behavior. Scored by the Forester Cyclist Proficiency Scale, with 70% minimum passing score, the populations received the scores shown in Table 4:

Proficiency of Cycling Populations


Num. Cyclists

Points Earned

Points Lost

Score %











Palo Alto










The club cyclists showed that the vehicular-cycling standard can be easily met. The general public cyclists showed how badly that standard is violated by the general bicycle-riding public.

Bikeway advocates argue that this study "is based on a far too small and limited sample of cyclists to yield any particularly meaningful results -- even if the methodology were universally accepted, which of course it isn't (even within the vc community)" (Geary, public comments) Complaining of statistical confidence limits of 95% and 99% in a traffic behavior study? That's really clutching at straws. Methodology questioned? Recording that cyclist #64 entered an intersection through a stop sign without changing his pedal cadence and without turning his head to look each way? That's questionable? Observing each cyclist until the end of his trip and then starting to observe the very next cyclist seen is sufficiently nonrandom for bias to build up? Just because the bikeway advocates aren't interested in such data doesn't mean that it is not valid data. (They aren't interested because they want incompetent cyclists and aren't interested in increasing competency.) That's more clutching at straws.

Evidence from Cyclist Training

It is often claimed by bikeway advocates that traffic-safe cycling is an elitist activity that can be performed only by people of far greater than normal abilities. The government avoids this bald statement, but it implies (FHWA 1992) exactly this. That document says that the bicycle transportation system must be designed for a using population in which 95% of the users will always be inexperienced and incompetent, unable to obey the traffic laws. That is the performance difference between A cyclists and B & C bicycle riders. The inexperience claim is as absurd as claiming that 95% of married persons will remain virgin.

The bikeway argument presents only two logical possibilities: either riding a bicycle makes one incompetent, or the task of cycling in traffic is much more difficult than the task of motoring in the same traffic. Those who maintain that competent, lawful cycling is an elitist activity must demonstrate either or both of these possibilities. Despite the fact that either or both of these assumptions have been the basis of the government's policy regarding bicycle transportation for at least sixty years, I have never seen any attempt to demonstrate either of these hypotheses. Almost the only argument offered is that cars are heavier and faster than bicycles. While this is reasonably related to the injuries likely to be incurred in case of a collision, it says nothing at all about how to avoid the collision. Furthermore, both hypotheses have been proved false in many ways.

Task Difficulty

The traffic-cycling instructions given in Effective Cycling are simply those for driving vehicles, with slight adaptations because bicycles are narrow enough that it makes a difference which side of a traffic lane the cyclist chooses. The fact that those instructions can be stated as five simple principles shows that if there is any difference in the degree of skill required, it is motoring that is more complicated and difficult. However, motoring could be taught according to the same principles given for cyclists; motoring instructors just haven't so organized their tasks. It is often remarked that children who have been taught to cycle properly have very little to learn when they take up motoring.

Ability to Learn

Obviously, bicycle riders over the age of fifteen years have the same visual, mental, and control abilities as motorists. The tasks are largely the same, except that cyclists also provide the motive power. From the beginnings of motoring until 1970 or so, both France and England raised generations of the public to obey the traffic laws for drivers of vehicles when riding bicycles; that was the public standard, without question.

The reason that American bicycle riders, since 1940 or before, have not obeyed the traffic laws, is that they have been taught that doing so will result in their death. American bike-safety training has been based on the cyclist-inferiority superstition: "The cyclist who rides in traffic will either delay the cars, which is Sin, or, if the cars don't choose to slow down, will be crushed, which is Death, and the Wages of Sin is Death." According to this, the prime duty of cyclists, to prevent them being killed, is to stay out of the way of same-direction motor traffic. Forester has discussed this since 1976. The current discussion is in Effective Cycling (Forester 1993, Chapter 43), and in Bicycle Transportation (Forester 1994, Chapter 12). Devoting all attention to keeping the roadway clear for motorists prevents the cyclist from operating competently and safely, and causes him to commit very dangerous acts, as in turning left from the curb lane without looking behind, which were the prevalent errors in the 63% of left turns done improperly in Palo Alto and 48% done improperly in Davis (Forester 1978-82)

The question of ability to learn therefore reduces to the question of age; how old must a child be to learn how to drive a bicycle vehicle in traffic. Forester and Lewiston (1980) and Forester (1981) demonstrated that classes of children aged from eight years to thirteen years learned to ride properly in fifteen class hours of instruction. The instructional methods are given in the Effective Cycling Instructor's Manual. (Forester 1977-80). The skills of the students in each class were tested by bicycle driving tests in real traffic (just like good motor-vehicle driving tests), and the class average scores on these tests were about 95%, with 70% as the minimum passing score. Eight-year-olds were tested and qualified to ride on two-lane residential streets; ten-year-olds on multi-lane streets with medium-speed traffic; thirteen-year-olds on multi-lane streets with fast traffic. All classes of children rode far better than the populations of adult cyclists around them, whose scores averaged about 60%.

Conclusions About Cyclist Competency

The evidence shows that bicycle riding in traffic is no more difficult than motoring in the same traffic. The evidence shows that even young children can learn to cycle properly in traffic in no more than the time required to learn motoring, and that children so trained cycle far better than the average adults cycling today. The fact that trained cyclists operate correctly shows that they have learned how traffic operates. This not only causes them to operate properly, but it enables them to understand when other drivers are not operating properly, so that they have a greater probability of detecting and avoiding the mistakes of other drivers.

In short, the assertions that cyclists must be incompetent are demonstrated to be false, and it has been shown that most people, starting at early ages, can learn to operate a bicycle in a competent and lawful manner with approximately the same expenditure that they would require to learn the same skills while driving a motor vehicle.

The Evidence About Ability

Bikeway advocates argue that persons who successfully ride in traffic must be near the limits of human capability in mental skills (the supposed ability to dodge cars), physical power (must be able to match the speeds of cars), and aggressive temperament (fighting the traffic). Such statements occur frequently in informal correspondence and debate, but are generally skipped over in formal papers. Note that the FHWA (1992) manages to avoid using these terms by classifying cyclists as either experienced or casual and beginning and child, but what else would this classification mean than unskillful and low-powered? Aggression was first formally asserted by bikeway advocate and economist Michael Everett about 1980 in bikeway advocacy papers published in the economic journals.

The evidence developed shows that ordinary people, substantially unselected except by the desire to cycle better, from children to elderly, after reasonable training, have shown, by actual test in real traffic, to drive their bicycles according to the rules of the road for drivers of vehicles. And it should be obvious that obeying those rules is a cooperative rather than an aggressive activity. In short, all the arguments of the bikeway advocates about human abilities have been shown to be false.


  1. Bikeways of practical, street-level design have not been shown to either reduce the accident rate at the same travel speed or to allow increased speed at the same accident rate, in comparison with cycling on the roadway with the rights and duties of drivers of vehicles.
  2. The arguments of bikeway advocates have been shown to be without scientific basis.
  3. Acquiring competence in cycling on the roadway with the rights and duties of drivers of vehicles has been shown to be by far the most effective means of reducing accidents to cyclists.
  4. Most people, from early ages, can learn in reasonable time to ride competently and lawfully on the roadway with the rights and duties of drivers of vehicles.

The preceeding four conclusions lead inevitably to the grand conclusion that society should adopt the vehicular-cycling principle, that "Cyclists Fare Best When They Act and Are Treated as Drivers of Vehicles," and design its bicycle transportation programs to implement that principle.


American Automobile Association; Children in Traffic, a film originally produced by the German Automobile Association

Association of American State Highway and Transportation Officials; Guide for the Development of New Bicycle Facilities; Washington; 1981 to present

California, State of; Bikeway Planning Criteria and Guidelines; Sacramento; April 1972

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Chlapecka, T. W., S. A. Schupack, T. W. Planek, H. Klecka & J. G. Driessen; Bicycle Accidents and Usage Among Elementary School Children in the United States; Chicago, National Safety Council; 1975

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Forester, John; Effective Cycling; Cambridge Mass; The MIT Press 6th ed 1993. First ed, 1976.

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Geary, Riley R.; US Bicycle Traffic Fatalities: Trends & Characteristics; VeloCity 2000

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