I came across this article and found it insightful: https://www.cyclingnorthwales.uk/campaigning/cycling-kinetic-energy-riders-reluctant-stop/
The article uses a rough calculation on the physics of kinetic energy to show why stop-start cycling is so annoying
Kinetic energy grows with the square of speed, so going at ~12mph and stopping and then restarting requires the same effort of cycling an extra 100 metres. A cyclist has to expend around 20 times as much energy as a pedestrian to stop and start.
This explains why shared use paths that stop at every side road are so bad to cycle on, and also helps explain why many cyclists go through red lights? Those shared use paths aren't great for novice cycles or children either, who struggle the most with balance which is tested each time they stop.
In short, it's easy to keep the bike in equilibrium but it's hard work to get going again. A fact seemingly overlooked when adding cycling infrastructure in this country and not understood by angry drivers.
I’m not having physics excuse running red lights.
I’m sure the physics is true but i think we should remember that we are 4 times more efficient than a pedestrian.
The same physics applies to motor vehicles of course. They are much more energy efficient whilst moving than if doing stop/starts. That's one of the reasons 20mph zones work, but it's still not an excuse for running red lights, ignoring pedestrian crossings etc.
The same physics applies to motor vehicles of course.
I think there's something wrong with your car if you get out of breath or feel the effort in your legs from accelerating!
Not that it's an excuse for running red lights.
Not sure any physics is necessary to explain why it is better not to have to stop..
I’m not having physics excuse running red lights.
It's usually a combination of physics and poor infrastructure. As noted above, cycle lanes that stop at every side road but also cycle lanes which force riders to wait even though the left turn aspect (for example) is clear and safe to proceed.
The UK needs an Idaho Stop law - basically if it's clear and safe, you can go. If there are any pedestrians at all (even ones crossing on their own red light) you must give way. If it is not safe (ie, it's a busy junction with lots of cars) you must give way.
Sometimes the simplest answer is to accept it happens and just formalise it a bit. It doesn't alter liability in the event of a crash, it doesn't create carte blanche for riders to plough through every red light, it just accepts and legislates what basically already happens.
Apparently the tory **** tom smarmydick had a big speel n’ rant regarding cyclists jumping red lights on his lbc show earlier,
Par for the course, won’t somebody think of the poor motorists
Par for the course, won’t somebody think of the poor motorists
I’ve only heard one, in person rant, about cyclists and red light. It was from a mate who doesn’t drive. He lives in the edge of London and his rant is that crossing the road, at crossing lights, is genuinely intimidating where he lives because, even when you are in a green man, the cyclists don’t stop or slow down
won’t somebody think of the poor motorists
I was going to say "what poor motorists?" then I realised I spend a fairly large part of my time on a bike and in a car trying to stay out of the path of poor motorists.
I’m not having physics excuse running red lights.
What if I were to tell you it's actually infinitely safer to ride your bike responsibly through an awful lot of red lights than it is to stop?
Do you blindly agree and comply with every single law the out of touch ****s in charge come up with?
Kinetic energy grows with the square of speed, so going at ~12mph and stopping and then restarting requires the same effort of cycling an extra 100 metres.
So on my 40 mile ride, where I stop left right and centre to admire a view, take a pic, negotiate a junction etc...I may really be riding 41 or 42 miles....excellent
What if I were to tell you it's actually infinitely safer to ride your bike responsibly through an awful lot of red lights than it is to stop?
I'd ask for a source and supporting evidence, or otherwise dismiss that as self supporting falsehoods that fitted with the general tone of the rest of the post.
I’d have thought that, unlike road biking, one of the major identifying factors of mountain biking is NOT riding at a uniform speed. Having to slow down and speed up is an integral part of mountain biking imo.
of course you would 🙄I'd ask for a source and supporting evidence,
I am your source. Common sense. And extensive experience from commuting and riding bikes on our roads for over 50 years. Are my evidence.
dismiss that as self supporting falsehoods that fitted with the general tone of the rest of the post.
Dismiss all you want. But that just makes you closed minded to new knowledge and experience from others. I could very easily write a PhD on the subject. Obviously no one would ever read it just like most PhDs.
Take me to the pub and I'd explain it to you over a pint.
I’ve only heard one, in person rant, about cyclists and red light. It was from a mate who doesn’t drive. He lives in the edge of London and his rant is that crossing the road, at crossing lights, is genuinely intimidating where he lives because, even when you are in a green man, the cyclists don’t stop or slow down
That's because they're obeying the laws of physics. Apparently. Except for the ones who are governed by the laws of impatience, which I suspect is the primary force in play for a lot of London riders.
What if I were to tell you it's actually infinitely safer to ride your bike responsibly through an awful lot of red lights than it is to stop?
'Responsibly' is doing quite a lot of heavy lifting there. I guess my question would be what proportion of cyclists can you realistically expect to ride 'responsibly' and make correct, safe decisions, the answer to which is that none of us actually knows. And what works on the mean streets of Idaho, may not be quite as effective in, say, central London.
Also, 'infinitely' sounds a little hyperbolic, no?
The traffic lights and stopping is actually a really good way of training. This kinetic energy argument is for lazy people. I remember struggling when I got back into commuting with the constant stop starts - legs were shot until I got used to it.
As @johnhe mentions, MTB riding is very much different pace, like mini intervals. Climbing a technical climb, power up the rough/difficult stuff then try and grab your breath on the easier stuff, then go again.
It's also why commuting is really good for fitness. Lots of mini intervals with all the traffic lights, or going for a gap.
'Responsibly' is doing quite a lot of heavy lifting there. I guess my question would be what proportion of cyclists can you realistically expect to ride 'responsibly' and make correct, safe decisions, the answer to which is that none of us actually knows. And what works on the mean streets of Idaho, may not be quite as effective in, say, central London.
every red light jumper I've personally seen has been of the hoodie up, headphones on, terrible bike handling and posture type rider. They either dont know any better or they know and they dont care.
these mythical riding gods who 20 years ago would have been the fastest messangers/couriers who can slip though junctions like a ghost, maintaining their average speed and efficiency... either dont exist or are so good at their craft that I truly dont notice them.
these mythical riding gods who 20 years ago would have been the fastest messangers/couriers who can slip though junctions like a ghost, maintaining their average speed and efficiency... either dont exist or are so good at their craft that I truly dont notice them.
Yes. Indeed. a rare and dying breed. With a 6th sense and phenomenal forward planning and risk assessment skill. Sorely missed in a world flooded with self blinkered, deafened, distracted and unaware types I'm not that surprised you haven't noticed them. Take the food delivery noodles around here for example. The majority are riding illegal throttle equipped Ebikes and almost never even move their face mask covered and fully hooded head to look anywhere but straight forwards the entire time they are riding apart from when looking DOWN at their phone. Most also wearing headphones so blissfully unaware of almost every other vehicle not in their direct line of vision.
Assuming you do actually commute in urban traffic fairly often. You must have seen the 'law abider' type RLJer? You know the one. The type who will either get off their bike and push it through the red light or scoot on one pedal sneakily through like they're the hooded claw from a hannah barbera cartoon. getting back on at the other side believing they have circumventing the law through a loophole. Those people make me laugh. As almost every single time it'd have been far safer if they had actually assessed the situation on approach, been fully aware of all that was around them, timed it properly and remained on their bike and ridden through.
these mythical riding gods who 20 years ago would have been the fastest messangers/couriers who can slip though junctions like a ghost, maintaining their average speed and efficiency... either dont exist or are so good at their craft that I truly dont notice them.
Couriering is a lost art these days.
There was a real skill in knowing which door to go to, which receptionist was the best to deal with, where the parcel was going and which was the most efficient route. Good couriers would know traffic light timings, likely traffic volumes, one way streets, which shortcuts you could take... It was like a super secret version of The Knowledge.
Everyone now is chugging around on illegally modified e-bikes, a massive Google Maps app running on the bars and using the throttle to compensate for their lack of flow.
Sigh. Kids today...
Why I run red lights, with some real world examples.
This one, why am I stopping to give way to 4 lanes of traffic heading for the M4? I want to take the left turn onto the cycle path that starts in that left hand junction just after the lihts. All stopping does is hold up the motorists, who to be fair only get about 10 seconds in the sequence at those lights! There's no logical reason not to allow a left turn on red there. There would even be space if they didn't have that pointless island between the left and bus lanes.
https://maps.app.goo.gl/nnQPYEBgQmvVwXQ89
Example 2. The Bus lane is also the cycle lane, when it works the lights change a couple of seconds ahead of the right hand lane. Except the lights wont change for cyclists. So the options are again, sit in the right hand lane, or just watch their lights and jump the red light whilst they're still checking Watsapp.
https://maps.app.goo.gl/upznvDGhwCMUgPGN9
Example 3, same road, same problem, reversed.
https://maps.app.goo.gl/NePvK3N22AZjD3jb7
Example 4, variations on a theme. This Toucan crossing takes so long to arrive at the crossing part of the sequence that everyone gets bored and legs it in the seconds between the last cars running the red light turning left and the next wave of cars turning right into the junction.
https://maps.app.goo.gl/nJAj9HtiqM4gVmQT9
This ones not even a red light jumping, but I've still been shouted at it. Coming down the cycleway you need to merge into the road just round the corner. This is never smooth as you can't have eyes in the back of your head. What you can (entirely legally) do is leave the path onto the crossing, and then turn left, and left at the give way line. The red light and it's solid stop line is for motorists at the crossing, I don't cross it.
https://maps.app.goo.gl/Vo45DXDioSFmAzxx5
This one is just a bit dangerous. Oncoming traffic is one way, the left turn is one way, right is pedestrianised (cycling permitted). All lights go green together (i.e. it's just an overly complicated pedestrian crossing). When turning right, o you a) obey the red light, and then stop in the middle of the junction surrounded by delivery trucks, busses and taxis all trying to turn across you, or b) cruise through the pedestrians into the pedestrianised street.
Actually it's a trick question, it's always busy with pedestrians as only busses are coming up behind you, not constant traffic, waiting for green won't actually mean there's any fewer pedestrians to navigate.
https://maps.app.goo.gl/4LbkLvT3dj5ZzsMX6