Is there a legal limit for how wide rear bike reflectors should be?

Ocsid

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Would 1m wide be too wide for the law? I don't see anything in the highway code about reflector width. Maybe it's down to traffic cop discretion?
IMO, albeit an uninformed opinion, one meter would be regarded as way too far an extension.

As a guide, mirrors on domestic cars are limited to an extension of 200mm beyond the vehicles body width.

If you take you bars as your bike's width, then add 200 mm to that would be effectively the order I would think most would consider a reasonable extension. Obviously, not coming off the bars but the frame towards the rear the actual item length to achieve the equivalent reach would be quite a bit physically longer.

But as said earlier I would add more than the reflective surfacing, a nice bright, rear facing flashing red LED ought to be an effective visual marker night and daytime.
 
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guerney

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IMO, albeit an uninformed opinion, one meter would be regarded as way too far an extension.

As a guide, mirrors on domestic cars are limited to an extension of 200mm beyond the vehicles body width.

If you take you bars as your bike's width, then add 200 mm to that would be effectively the order I would think most would consider a reasonable extension. Obviously, not coming off the bars but the frame towards the rear the actual item length to achieve the equivalent reach would be quite a bit physically longer.
That seems reasonable, but surely those lollipops aren't too wide for legality? They measure 341mm beyond the bike frame attachment point, therefore one either side would add 682mm to the overall width of the bike. For my bike, that's 872mm total width with lollipops.
 

matthewslack

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My solar trailer is 1.16m wide, although it is a thing rather than a projection from a thing.

The maximum width for a vehicle without the need to inform the police, and without the need for an escort vehicle, is 2.55m. But a bicycle is a carriage, not a vehicle.

Mirrors on cars pulling caravans are often extended to see past the caravan, and the largest modern caravans are 2.40m or so, so those mirrors extend 300mm or so from the car.

Sone taxi drivers in my experience fall into the category of the 1% who will not change their ways until reported to the police and charged. Points on their licences threaten their livelihood, whilst their behaviour threatens cyclists' lives.

Round here on the single track with passing places route I go shopping, they will drive without slowing in opposite direction to me on the narrow bit between passing places. 40mph closing speed with not much gap.
 

guerney

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Sone taxi drivers in my experience fall into the category of the 1% who will not change their ways until reported to the police and charged. Points on their licences threaten their livelihood, whilst their behaviour threatens cyclists' lives.
They only sleep those guys get, is while driving
 

Ocsid

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That seems reasonable, but surely those lollipops aren't too wide for legality? They measure 341mm beyond the bike frame attachment point, therefore one either side would add 682mm to the overall width of the bike. For my bike, that's 872mm total width with lollipops.
We are at cross purposes here, I am talking about levels of extension towards the passing vehicle threat, not the overall width. Seeing it is on the passing vehicle side that needs to encourage them to stay further out,
 

guerney

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We are at cross purposes here, I am talking about levels of extension towards the passing vehicle threat, not the overall width. Seeing it is on the passing vehicle side that needs to encourage them to stay further out,
I'm tempted to go back to my original plan of gaffa taping a thick pool float noodle covered with red reflective tape on the passing side. I couldn't be accused of causing damage with a pool noodle. Both sides are passing sides on rounabouts.
 

soundwave

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dongle cuts out at 36mph
 

WheezyRider

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I'm thinking of making very wide reflectors to keep cars from passing so close, because yet another Uber driver whizzed by too close to me last night. Does anyone know how wide is too wide for rear bike reflectors? How wide is illegal? I'm going to have to make them, because these lollipop style things can't be vertical on my bike, and they're not wide enough anyway



You might be interested in my thread from a couple of years ago:


I 3D printed a "traffic boom" as I was fed up with close passes and what was available on the market just wasn't up to the job. I designed it to be max 39 cm beyond the end of my handlebars, since the vehicle regs say if you have something protruding more than 400 mm it needs to be fitted with warning triangle.

It has a hinge, to allow for filtering through traffic.
 

I893469365902345609348566

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You might be interested in my thread from a couple of years ago:


I 3D printed a "traffic boom" as I was fed up with close passes and what was available on the market just wasn't up to the job. I designed it to be max 39 cm beyond the end of my handlebars, since the vehicle regs say if you have something protruding more than 400 mm it needs to be fitted with warning triangle.

It has a hinge, to allow for filtering through traffic.
Your solution is brilliant! Has your long arm been troubled by the long arm of the law? I particularly like that your safety device folds for traffic filtering. I think the lollipod would extend about 45cm from the centreline of my bike, which doesn't seem long enough to keep the buggers away. I could graft a length of plastic on. You should offer your safety arms for sale!
 

guerney

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I've just measured the width of my handlebars - 85cm with Zefal Dooback 2 wing mirrors tip to tip. If the fuzz can't object to that, I don't see how they can object to a rear reflector bar being as wide. The springs make it safe-ish for traffic filtering, but it won't be as wide as the handlebars with Zefals, so I doubt I'd hit cars with the reflector bar. I can't be sure how long the rear reflector bar will be until the aluminium bar arrives - perhaps about 62cm wide when assembled. I should have ordered a slightly longer bar doh! I'm going to try it with a flashing LED strap ziptied along it's length, mostly on the passing side - it's inbuilt rechargeable battery lasts at least 6 hours, but the tiny case containing the electronics might need additional waterproofing, because it isn't being worn vertically or at 45 degrees as designed (the charging port and rubber cover are on the base).

If that doesn't work, I'll buy a longer 1/4 ich thick aluminium bar!


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DBye

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@I893469365902345609348566 , how far away from the kerb are you in your videos? I remember reading a study that drivers tend to mirror the distance between you and the kerb (humans like symmetry), so the closer you ride to the kerb, the closer the passes.

My worry with the reflector arms is that they could get caught on a passing driver and I get pulled along with them! I know they are more likely to break or have an inbuilt safety, but I still don't like the thought of it!
 
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Ocsid

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My worry with the reflector arms is that they could get caught on a passing driver and I get pulled along with them! I know they are more likely to break or have an inbuilt safety, but I still don't like the thought of it!
I share that concern, most certainly with using what I envisage an aluminium bar infers.
For me it would be something more like an 8mm section potting bamboo cane job, something that will snap long before endangering me.
 
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WheezyRider

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Your solution is brilliant! Has your long arm been troubled by the long arm of the law? I particularly like that your safety device folds for traffic filtering. I think the lollipod would extend about 45cm from the centreline of my bike, which doesn't seem long enough to keep the buggers away. I could graft a length of plastic on. You should offer your safety arms for sale!
I've had police stare at me as they drove past, but no one has stopped me and made a complaint. I've thought about commercialising, but there are a lot of barriers to doing that. One is my day job. Another is that it would need to have a universal fitting designed to fit any bike, which will take some developing, not all bikes have space on the stem between the cross bar and the diagonal tube. I have some ideas, but no time to work on them. Then there is mass production, to make it cost effective, you'd have to tool up to make large numbers, which needs a fair bit of capital and connections. Then you need IP protection, otherwise some guy in China will just flood the market with cheap copies. I don't think it's something you could protect easily. The idea has been around for years. You'd have to patent a specific mechanism or whatever.

But the concept is sound and it works extremely well.
 

WheezyRider

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@I893469365902345609348566 , how far away from the kerb are you in your videos? I remember reading a study that drivers tend to mirror the distance between you and the kerb (humans like symmetry), so the closer you ride to the kerb, the closer the passes.

My worry with the reflector arms is that they could get caught on a passing driver and I get pulled along with them! I know they are more likely to break or have an inbuilt safety, but I still don't like the thought of it!

The arm pivots forward by 90 Deg, so if it gets hit from behind, it simply swings forward. Then with the Mark III version, I replaced the old plastic reflector on the end (shown in those photos - which was gaffer taped on) with a 3D printed bright yellow twin reflector unit which slides onto the wooden pole. So if the reflector did get caught, the force would just slide it off the end of the pole and it would come off.

However, no car has ever made contact with the tip of the traffic boom, they tend to give you a wide berth and even on the odd occasion where they have deliberately come close, they were still at arms length and not inches from the handlebars.

Fitting a Pass Pixi also helps:


When drivers know they are being watched an recorded, it tends to focus minds on proper over taking behaviour. Cameras tend to be small, so having the warning sign clearly visible does make a difference, especially now the Highway Code has made it clearer that drivers can be prosecuted for not giving enough space.
 

flecc

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Oct 25, 2006
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Way back in the 1960s and '70s in London there was a well known older cycling activist named Bob something or other. He'd equipped his bike with a large rectangular shaped frame of tubing around four feet wide, a little taller than him and the length of the bike.

Although not commuting to any work, he used to ride it daily on commuter routes in the rush hour, forcing drivers to take the size of the rectangular space he felt he needed into account.

He rode quite slowly with the extra weight, but of course all cycling was slower back then, none of today's grim faced, helmeted and lycra clad Tour de France wannabees desperately trying to ride at 20mph or more.
.
 

guerney

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My worry with the reflector arms is that they could get caught on a passing driver and I get pulled along with them! I know they are more likely to break or have an inbuilt safety, but I still don't like the thought of it!
The 1/4 inch aluminium bar has arrived and it 30.3 cm long. I'm not too worried, because the springs I'll be inserting the bar into will flex. I may use very thin zipties or something, to secure it to the rear pannier rack, which will break away in an impact - it'll pretty much be about the same length as the brittle plastic. Perhaps the brittleness of the plastic was a safety feature, and not chosen because it was cheap and nasty?

It's going to be hard work getting this bar 3/4 inch into those springs. Grease and elbow grease methinks. It's the same thickness as the cr*ppy plastic it's replacing, so should eventually fit. The plastic was easily drilled out.


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