Bicycle restrictor

General cycling advice ( NOT technical ! )
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mjr
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Re: Bicycle restrictor

Post by mjr »

pwa wrote:Just to explain things from the other side (as I've done before) A Frames (as they are commonly known) are designed to inhibit motorcycle use whilst allowing bicycles, pushchairs, wheelchairs and most motorised wheelchairs to get through. To work properly they have to be installed correctly, and thet sometimes aren't.

No, to work properly, they have to achieve the logically impossible goal of allowing through 700mm-wide bicycle handlebars and 850mm-wide mobility scooters while blocking motorcycle handlebars that can be as narrow as 520mm.

Those barriers can never work, but so many manufacturers and council officers (and barrier apologists) have invested so much money and reputation in that snake oil that they keep getting used and it's a bugger to get them removed. Point out to the council if they are blocking disabled users from the path and see if any of the local disability groups are willing to help take it forwards. Make a noise in the press. Most councils will fold long before getting taken too far, but it's best done by disabled users or those with children whose trailers get blocked, not just stereotypical cyclists, sadly.

Or you can just do what has happened in some places... and battery angle grinders are getting cheaper every day. ;-) Anyone know if the right to clear illegal obstructions from a highway, bridleway or footpath would legitimise such removal by an obstructed user?
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
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pwa
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Re: Bicycle restrictor

Post by pwa »

mjr wrote:
pwa wrote:Just to explain things from the other side (as I've done before) A Frames (as they are commonly known) are designed to inhibit motorcycle use whilst allowing bicycles, pushchairs, wheelchairs and most motorised wheelchairs to get through. To work properly they have to be installed correctly, and thet sometimes aren't.

No, to work properly, they have to achieve the logically impossible goal of allowing through 700mm-wide bicycle handlebars and 850mm-wide mobility scooters while blocking motorcycle handlebars that can be as narrow as 520mm.

Those barriers can never work, but so many manufacturers and council officers (and barrier apologists) have invested so much money and reputation in that snake oil that they keep getting used and it's a bugger to get them removed. Point out to the council if they are blocking disabled users from the path and see if any of the local disability groups are willing to help take it forwards. Make a noise in the press. Most councils will fold long before getting taken too far, but it's best done by disabled users or those with children whose trailers get blocked, not just stereotypical cyclists, sadly.

Or you can just do what has happened in some places... and battery angle grinders are getting cheaper every day. ;-) Anyone know if the right to clear illegal obstructions from a highway, bridleway or footpath would legitimise such removal by an obstructed user?


In spite of what you say I have seen them work. I have seen them reduce, almost to zero, motorcycle use on paths, whilst still allowing locals on mobility scooters to get through with no problems. I suggest that 700mm wide handlebars are exceptionally wide, and just like someone trying to park a Rangerover in a supermarket car park you cannot expect the whole world to alter things just because you choose to go for something very wide. If you want to go through A Frames with your bike, make your bike suitable. The power to do so is in your hands.
hamster
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Re: Bicycle restrictor

Post by hamster »

pwa wrote:
hamster wrote:I have similar problems with some locally, however wheeling the bike vertically on its back wheel solved the problem. There is a knack to flicking the bike onto its rear wheel - a quick shove on the saddle simultaneously pulling up on the bars does the trick. As somebody was killed on the stretch by an illegal motorbike, I cannot blame the authorities for putting it in.


Hamster, do you feel that cutting your bars down a little would help? Or is that impractical? Even on a tandem I have my straight bars cut down because I prefer them that way, and as a by-product I find correctly installed A Frames no problem with that bike. I have to stop and put a foot on the ground, of course.


Frankly no. It depends on what you ride. In my case it's a rigid singlespeed that I ride off-road. I switched to 620mm bars on my Orange P7 from 560 as it handled like a scalded cat (fun but too tetchy on the technical stuff). However, the current fashion for 700mm+ bars is definitely a stretch too far for me.

My main bugbear is one particular A-frame which is around 50mm too narrow in my judgment. Tilting the tandem sideways is the only way through.
pwa
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Re: Bicycle restrictor

Post by pwa »

hamster wrote:
pwa wrote:
hamster wrote:I have similar problems with some locally, however wheeling the bike vertically on its back wheel solved the problem. There is a knack to flicking the bike onto its rear wheel - a quick shove on the saddle simultaneously pulling up on the bars does the trick. As somebody was killed on the stretch by an illegal motorbike, I cannot blame the authorities for putting it in.


Hamster, do you feel that cutting your bars down a little would help? Or is that impractical? Even on a tandem I have my straight bars cut down because I prefer them that way, and as a by-product I find correctly installed A Frames no problem with that bike. I have to stop and put a foot on the ground, of course.


Frankly no. It depends on what you ride. In my case it's a rigid singlespeed that I ride off-road. I switched to 620mm bars on my Orange P7 from 560 as it handled like a scalded cat (fun but too tetchy on the technical stuff). However, the current fashion for 700mm+ bars is definitely a stretch too far for me.

My main bugbear is one particular A-frame which is around 50mm too narrow in my judgment. Tilting the tandem sideways is the only way through.


I suggest you have a look at the A frame and see if it has a manufacturer's mark. If it does, try to get the spacing specs online, then go out with a tape and measure it. If it has a narrower gap at handlebar height than on the specs, chase it up with the Local Authority. It does sometimes happen. I've corrected and A Frame with that problem in the past. Sometimes one side is not square with the other so that from one direction it narrows as you go through, and from the other it widens. Again, something to report.
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julk
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Re: Bicycle restrictor

Post by julk »

tyreon,
I suspect that any action via the local council will be very slow and probably not taken so…

If your stem is a quill stem then take an appropriate spanner or allen key and loosen the stem to turn your handlebars sideways to get through the obstacle before straightening and tightening your stem for further riding on the safe route.

If your stem is an ahead type which clamps the headset bearing as well then fit a http://www.sjscycles.co.uk/problem-solvers-locking-headset-spacer-for-1-1-8-inch-black-prod18246/ locking headset spacer at the bottom replacing a headset spacer.
This gadget will hold the bearings in adjustment whilst you undo the stem and turn the handlebars as above.

I hope you get back on your safe route.
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RickH
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Re: Bicycle restrictor

Post by RickH »

hamster wrote:Frankly no. It depends on what you ride. In my case it's a rigid singlespeed that I ride off-road. I switched to 620mm bars on my Orange P7 from 560 as it handled like a scalded cat (fun but too tetchy on the technical stuff). However, the current fashion for 700mm+ bars is definitely a stretch too far for me.

The widest bars in my fleet (3 bikes) is 530mm on my 1986 Muddy Fox MTB and, as I said before, I've never had cause to think that I needed something wider. If anything the handling feels more like the front wheel is stuck in a rut than too lively. On the tandem the pilot bars are cut down to about 49cm (straight bars with Origin8 drop bar ends) - I only didn't cut those any narrower to leave them a few mm wider than the stoker bars (so that they are the limiting factor & I won't get stuck halfway through anything narrow :? ). My road bike has drops that are about 44cm wide edge to edge.

hamster wrote:My main bugbear is one particular A-frame which is around 50mm too narrow in my judgment. Tilting the tandem sideways is the only way through.

I must admit to coming across one A-barrier (in Walkden, Salford) that was set too narrow for even my road bike drop bars, they cant have had more than 40cm space at the top. It was on the route of an organised ride & some people had difficulty getting through, never mind their bikes!
Former member of the Cult of the Polystyrene Head Carbuncle.
Bmblbzzz
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Re: Bicycle restrictor

Post by Bmblbzzz »

I'd point out that getting through A-frames is not only a matter of width; it's also about dexterity and balance.
MartinC
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Re: Bicycle restrictor

Post by MartinC »

pwa wrote:...................In spite of what you say I have seen them work..................................


Are you saying that you've a seen lots of motorbikes approach them and been unable to go through or, even better, that there was an accurate count of motorbikes on the path before and after the installation and it went from x to zero? Or are you assuming cause and effect from some correlation between unquantified complaint levels before and after installation?
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Mick F
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Re: Bicycle restrictor

Post by Mick F »

julk wrote:If your stem is an ahead type which clamps the headset bearing as well then fit a http://www.sjscycles.co.uk/problem-solvers-locking-headset-spacer-for-1-1-8-inch-black-prod18246/ locking headset spacer at the bottom replacing a headset spacer.
What a brilliant idea! :D
Wish they would come in 1" as well.
Mick F. Cornwall
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mjr
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Re: Bicycle restrictor

Post by mjr »

pwa wrote:In spite of what you say I have seen them work. I have seen them reduce, almost to zero, motorcycle use on paths, whilst still allowing locals on mobility scooters to get through with no problems. I suggest that 700mm wide handlebars are exceptionally wide,

Not really, it's only two inches each side wider than the very common hybrid 600mm - but remember that mobility scooters may be up to 850mm wide and the official width of a cyclist's dynamic envelope is a metre, so 700mm handlebars should fit through any non-discriminatory barriers easily. They don't. Plenty of 600s are too close to ride through.

All the A barriers around West Norfolk that I can think of are essentially absurd because they are at one end of a track with other unbarriered accesses or right next to a hedge that motorbikes drive through. If any A-barriers are ever set narrow enough to reduce motorcycle use, then they will be blocking some users and causing others to crash.
and just like someone trying to park a Rangerover in a supermarket car park you cannot expect the whole world to alter things just because you choose to go for something very wide. If you want to go through A Frames with your bike, make your bike suitable. The power to do so is in your hands.

Both getting the barrier rendered harmless (officially or informally) or using another route (not an option for every case, I know) are far simpler and surely it's better to remove a discriminatory barrier once instead of trying to adapt every bicycle in a town with thousands of riders? And that's without considering tourists who would get a nasty surprise if they dare to visit with a perfectly normal bicycle that doesn't comply with the pwa narrowness rule.

And who builds a supermarket now with spaces too narrow for a Range Rover anyway? The 2016 Range Rover is 2.2m wide. The minimum parking space width in the planning policies is 2.5m and they're usually wider because few car parks rows are exact multiples of 2.5m and it cuts down the number of Range Rover owners grumbling about their doors getting dinged. We have altered things many times for motorists and our increasingly-wide cars, so why say we can't for cyclists?
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
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Bmblbzzz
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Re: Bicycle restrictor

Post by Bmblbzzz »

Well put, mjr.
pwa
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Re: Bicycle restrictor

Post by pwa »

MartinC wrote:
pwa wrote:...................In spite of what you say I have seen them work..................................


Are you saying that you've a seen lots of motorbikes approach them and been unable to go through or, even better, that there was an accurate count of motorbikes on the path before and after the installation and it went from x to zero? Or are you assuming cause and effect from some correlation between unquantified complaint levels before and after installation?


On the main example I've been using, I'm going off what I was told by neighbours whose houses formed the sides of a particular path, and what I was told by residents of other parts of the estate where we put about four A frames on paths where motorcyclists had been doing a circuit. I also received feedback from a community councilor. Obviously the A Frames are not 100% motorcycle proof, and a determined motorcyclist can often wiggle through. But having to repeat that each time he encounters one of several A Frames can make a route less attractive to him. In this instance what seemed to happen was a displacement, with the motorcycles being taken, instead, to an area of open scrubland further away from the houses. And the A Frames were accessible for mobility scooters (not just the tiny ones), wheelchairs, pushchairs and all the bicycles I saw trying to use them. It's not a perfect solution and I wish it were not necessary. In some locations there is no need.
MartinC
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Re: Bicycle restrictor

Post by MartinC »

pwa wrote:
MartinC wrote:
pwa wrote:...................In spite of what you say I have seen them work..................................


Are you saying that you've a seen lots of motorbikes approach them and been unable to go through or, even better, that there was an accurate count of motorbikes on the path before and after the installation and it went from x to zero? Or are you assuming cause and effect from some correlation between unquantified complaint levels before and after installation?


On the main example I've been using, I'm going off what I was told by neighbours whose houses formed the sides of a particular path, and what I was told by residents of other parts of the estate where we put about four A frames on paths where motorcyclists had been doing a circuit. I also received feedback from a community councilor. Obviously the A Frames are not 100% motorcycle proof, and a determined motorcyclist can often wiggle through. But having to repeat that each time he encounters one of several A Frames can make a route less attractive to him. In this instance what seemed to happen was a displacement, with the motorcycles being taken, instead, to an area of open scrubland further away from the houses. And the A Frames were accessible for mobility scooters (not just the tiny ones), wheelchairs, pushchairs and all the bicycles I saw trying to use them. It's not a perfect solution and I wish it were not necessary. In some locations there is no need.


Well, yes. Extrapolating from this to a general conclusion that A frames work everywhere isn't robust. You're clearly talking about a very limited population of offenders who had a readily available alternative and concluding from some very subjective second hand reports that the problem has gone away permanently.

If you want to generalise from this experience it would be better to propose the mechanism that prevented their access, evidence it from reliable data and then show how it would be equally valid elsewhere.

The notion that an A Frame can allow access by legitimate users but prevent motorcycle access is absurd. It's classic example of the old syllogism "this is terrible, something must be done, this is something, therefore it must be done".
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meic
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Re: Bicycle restrictor

Post by meic »

And who builds a supermarket now with spaces too narrow for a Range Rover anyway? The 2016 Range Rover is 2.2m wide. The minimum parking space width in the planning policies is 2.5m and they're usually wider because few car parks rows are exact multiples of 2.5m and it cuts down the number of Range Rover owners grumbling about their doors getting dinged. We have altered things many times for motorists and our increasingly-wide cars,


I like that, get them to drive their Range Rover into the space and then laugh as they have to climb out of the tailgate. :lol:
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pwa
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Re: Bicycle restrictor

Post by pwa »

Martin,

I did not extrapolate to a general conclusion that A Frames work everywhere. I have already said that badly installed ones are a problem that should be reported. I have also said that installing them adjacent to flimsy fences is pointless. And I've said that there are many places where they are not needed. And if you take the care to read my previous posts you will find that on two occasions I have said that A Frames do not completely prevent motorcycle access, so your implied assertion that I did say that is, to use your word, absurd. And I've said that I wish they were not needed anywhere.

My job was the very practical one of improving landscape and recreational infrastructure for communities, not walking around with a clipboard conducting detailed studies of work already done. We didn't have the time or the money for that. We did the very simple thing of talking to people and listening to what they had to say. And when you get lots of people all saying the same thing you begin to think that you have a clear picture of their experience. It's what is known as "listening to communities". When the residents living close to the A Frames say that the motorcycle problem is much reduced, I tend to think that they are the people to listen to. They live there, day and night.

I can easily think of locations where an A Frame would not have the desired effect of reducing motorcycle use. And I can think of other locations where it probably would. I agree with anyone who says that they are used too freely.
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