"Bikes use more road space than cars when moving... http://buff.ly/2hdCksz << Not plugged this for a while... bikes are waste of road space!"
The buff.ly link takes you to his blog. To save flicking between them I'll copy it across verbatim and have a look at the points he's made.
Ok...
Got into tweet exchange with some loony^H^H^H^H^H misguided cyclists over insurance, licencing etc... Got to the usual 'bikes take less space so cause less congestion bit with the usual image...
I'll ignore the above for the time being and look at the theme for this particular blog post, the idea that bikes take up more space than a car.
However this image has always annoyed me as it shows *parked* vehicles, not moving ones. If you are designing a car park, fine, but for road planning it it nonsensical.
So the figures... (from first reliableish looking google search result in each case).
An urban cyclist rides at 10mph, a bike is approximately 6' long, and needs about 13' to brake from 10mph (thinking distance assumed to be the same car/bike so ignored) - and minimum recommended cycle path width is 5' (1.5m) - so at 10mph a bike (carrying a single person) uses 5' by 19' of road space. About 1.5m by 6m
I'll take the braking distance and dimensions for granted but using recommended cycle path width as a metric for a bicycles width is problematic, it assumes that recommendation has A) been followed and B) that a cycle lane exists at all. The widest handlebars that are used on any appreciable number of bicyles would be around 800mm and that's at the extremes of a mountain bike handlebar, for a road/commuter bike 500-600mm is much more common. As with the reaction times ignored by @pperrin I'll ignore the distance from the kerb as both cars and bikes will need to leave some space. I think therefore, it's safe to say that the 5' wide assertion is a bit of an exaggeration.
A small car is about 5' wide and 13' long, at 10mph it needs 4' of breaking distance (thinking distance ignored again as same as for bike, so cancel out). So at 10mph a small car (regardless 1-4 occupants and luggage) uses 5' by 17' of road space. About 1.5m by 5m.
A small car is indeed about 5ft or 1.5m wide if you look at the very smallest cars on sale in the UK. The narrowest being the Citroen C-Zero/Mitsubishi MiEV/Peugeot ion. Hands up if you see one of those daily? The next narrowest car is the Smart ForTwo at about 1.55m wide. That measurement, however, ignores the wing mirrors so unless you plan to clatter into other road users on your travels you'll need to leave a space of 1893mm or just over 6 feet. The smart fortwo of course as the name suggests only carries two passengers and has a tiny boot, so hardly much advantage over a bicycle in that respect, particularly compared to a cargo bike like a Surly Big Dummy. The Smart car does, of course, come in shorter than the 13' quoted above but as we've noted, it doesn't hold four passengers.
So to travel safely a bike uses over 1.5sqM of road more than a car (whether the car is carrying 1 or 4 people!).
I think therefore we can ignore this conclusion. If a bicycle width is measured by the recommended lane width rather than its handlebars (it's actual widest point), then surely we should be measuring a car by the width of the lane that it too inhabits? Or if we are sticking to actual vehicle/bicycle widths then we should make sure that we include the wing mirrors as well. It's clear that the narrowest common car is wider than an uncommonly wide bike and it'll be longer than a bicycle even if it scarifices 50% of it's passenger capacity and luggage space. This whole argument of course also hinges on the fact that the smallest car you could possibly have isn't that much bigger than a bike which ignores the reality of how big the most likely to be used motor vehicle is on Britain's roads. To turn this on its head it's as silly as me saying bikes take up only 5% of the space a Chieftain Main Battle Tank takes up on the road.
In addition a car can reliably and consistently go at a particular speed - right up to the speed limit (or other safe speed) so meaning no passing is required. Whereas a bikes speed depends on the fitness/strength/recovery of the cyclist - so closing up/passing may be frequently needed - causing confusion, stress and conflict.
This is an interesting statement. Have you ever been on a motorway (where bicycles are prohibited and therefore can't be blamed for holding everyone up) and found that no cars, lorries or coaches have ever had to pass each other? Instead they sit in an orderly queue and everyone joins/leaves the carriageway without the slightest change in velocity? Of course you haven't, it's nonsense.
The last sentence also worries me greatly, the concept of driver licencing as being a guarantee of road-user quality is clearly flawed. What is the point of a system whereby it allows someone to drive on the roads and that when they come across a slower vehicle (bicycle, school bus, invalid carriage, tractor, etc) they can be expected to suffer "confusion, stress or conflict". These don't sound like people that should be allowed to pilot vehicles capable of 270mph (as of course, pass a single test in a 60bhp Nissan Micra and you've done enough to be allowed to drive a Bugatti Veyron supercar)
And if a cars are travelling faster, then they are (of course) using the space they occupy for less time... So at 10mph a bike and solo driver may be on par, but in most other circumstance, the car uses less road space than a bike - a quarter with 4 passengers, and half for each additional 10mph of speed.
I suppose this makes almost sense if you are talking about literally the space a vehicle occupies during a snapshot of it's travels but it ignores the practicality of the real world. The car will be taking up much less space at 100mph than it would at 30mph but really as a pedestrian/cyclist/driver what is going to make you hesitate more to join a road from a stationary position, a bicycle coming at you at 10-15mph or a car travelling upwards of 4x that speed? In effect the car is occupying all the space in front of it that it would need for a safe braking distance.
So there you go - bikes need smaller parking areas, but use generally use more road space to get you there later and unfit to do anything once you arrive!
This description of fitness is problematic. I'm assuming that @pperrin means that a bicycle can't shift as many people/bags of stuff. To be able to assert this you'd have to have data on what the average person does when they get where they are going by whichever means of transport they use. I haven't a clue where to find that data and would be interested to know if @pperrin knows either. For every carpenter that needs their large van of tools and equipment, I'm sure there are many more office workers who need to shift nothing larger than their knowledge or a laptop computer around.
**Edit** to put some linkable data in - the highway code breaking distances starts at 20mph, but going with that... And giving the bike figure the benefit of the doubt that it does include thinking distance.
Highway Code (UK government body): The breaking distance for a car at 20mph is 12m/40'
The CycleScheme (a pro-cycling group): The breaking distance for a bike at 20mhp is 18m/60'
(Notwithstanding the fact cars have anti-lock breaks, are regularly MOT tested and are driven by trained/licensed drivers who are required to be alert/sober etc.Whereas a bike has what ever brakes it happens to have, in whatever condition they happen to be in and may be ridden by absolutely anyone).
Notable bias here and a cringing use of breaks instead of brakes. Without wanting to sound pedantic not all cars have ABS brakes, MOT tests only verify the condition of a vehicle once a year and as the SMMT discovered a third of all drivers admit to driving with no MOT.
Training/Licencing for the majority of road users means a handful of lessons and one test in your teenage years and then you are free to drive until your dying day. Of course not having a licence doesn't physically stop you driving a vehicle as noted by the Telegraph when it reported 70,000 drivers get points despite not holding a licence, how many more out there just haven't been caught yet? It also ignores the fact that many cyclists, like myself, are also driving licence holders so have the exact same training, and possibly more than many car drivers.
The requirement to be alert/sober is also pretty worthless as an argument, when 20% of road accidents are caused by tiredness and when through drink driving 260 people are killed, 1100 are seriously injured, 8000 become lesser casualties and 70,000 (12%) tested drivers are over the drink drive limit it's clear that making something a requirement doesn't actually make it happen. @pperrin would have us believe that it was some sort of a magic bullet to road using saint hood. Would you prefer to take your chances against a poorly maintained bike or against one of the 70,000+ drink impared drivers bearing down on you in two tonnes of metal?
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