Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: Ben T on 14 January, 2019, 05:35:56 pm

Title: Mudguard skills
Post by: Ben T on 14 January, 2019, 05:35:56 pm
Would like to increase skills in mudguard maintenance/fitting.

My rear SKS bluemels cracked in two places. Shop has agreed to replace so will only cost a couple of quid in postage to replace.
One crack was midway between the (plastic, non-riveted) brake bridge mount, and went right through (but the tape used to fasten the light wire on held it together) and the other was just below the upper (riveted) stay mount, and hadn't quite gone right through.

I would ideally like to acquire the ability to (a) prevent them cracking in future, but also (b) scope out if there is any better semi-permanent way of attaching the dynamo light.
I guess as far (a) goes, make sure the stays aren't bending it / holding it under tension, but anything else?
I previously thought rivets were a source of cracks, but here, one crack has occurred near the rivet but another one away from it. I guess it could be that the one near the rivet occurred first, and that put increased pressure on the rest of the guard that caused the other one. Hmm...

As far as (b_ goes, previously I used this tape: https://www.amazon.co.uk/gp/product/B00940IEU0/ref=oh_aui_search_asin_title?ie=UTF8&psc=1 which has stuck, very well - in that it has remained completely in place and has actually held the guard together when it cracked - but slightly too well - in that it has peeled off little patches of the lacquer of the mudguard, leaving the silver inside showing.#
I would like to be able to remove and re-fit the guard ideally with minimal damage in order to be able to fly with the bike. I guess it's better than tape that comes off when it's wet, as if it peels any lacquer off in future I can just stick new tape over it, but if anybody knows any that doesn't do this, but still sticks well, would like to know. Does the lacquer contribute to the robustness of the mudguard or is it just for looks?
Title: Re: Mudguard skills
Post by: BrianI on 14 January, 2019, 06:03:05 pm
Pics of the mudguard fitting would be helpful. Can't ever say I've had any SKS mudguards snap in half. My rear dyno light is on the rear of my pannier rack...
Title: Re: Mudguard skills
Post by: Brucey on 14 January, 2019, 06:15:29 pm
IME the #1 cause of cracked chromoplastic mudguards is that they were not fitted correctly. Some top tips;


1) make sure the stays are secure and that they are not strained sideways when fitted; in other words they should be 'set' so that they sit in the correct place naturally, even when not attached to the mudguard

2) avoid straining the mudguard curvature esp near the brake bridge.  If necessary space the mudguard away from the chainstay bridge so that there isn't permanent strain on the mudguard.

3) chamfer/trim the mudguard if necessary so that it fits between the chainstays without being strained.

4)  if some strain is unavoidable, you can locally heat the mudguard (eg using a hairdryer) so that it takes a 'set'. It is less likely to crack vs being strained when fitted.

5) fit the (stainless steel, the plastic ones are crap) brake bridge mount so that the bottom of the slot is not exposed, if necessary by using washers either side of it, 

6) crimp the bridge support so that the mudguard doesn't rattle there

7) avoid having the stays differently bent one side of the bike to the other; this is commonly the case on disc brake bikes but it encourages the mudguard to flap from side to side more than it should.

8) make absolutely sure that your bike is in track; if it is slightly lopsided (eg a pannier on one side is enough) then again the mudguard will vibrate from side to side more and this (other than massive strain) is what destroys them most quickly.

9) use nylocks etc so that the mudguards are not likely to work loose

Basically if you slacken any one mounting bolt and the mudguard immediately moves under its own steam, there is some strain in it somewhere, and probably this can be reduced or eliminated, thus giving the mudguard an easier time of it.

I agree that the rear light is best put somewhere else; a lightweight reflector is much less likely to strain the mudguard.  Having broken a couple of mudguards with the light on (they seem to crack at the middle stay mounts when the light is attached, and strain all the other mountings more too ) I have my light on the seat stays.

I think that these mudguards are polycarbonate and therefore eventually embrittle and become likely to crack. Some solvents and UV light will speed this process up.  But I have had a set of chromoplastic mudguards last about 30 years (mostly outdoors) before I broke them; however when they broke they were as brittle as glass.

I'd also note that skinny mudguards and skinny high pressure tyres are a bit of a double-whammy; the mudguards see a lot more vibration damage with this kind of setup.

cheers
Title: Re: Mudguard skills
Post by: Ben T on 14 January, 2019, 06:35:34 pm
Thanks for the pointers on making sure they're not strained.

Agree the seat stay is better maintenance wise for the rear light, but can you counter my suspicion that there is a "blind point" where a road user (e.g. a car) could be in a position such that they can't see my rear light due to the mudguard or wheel being between them and the light source?

Is it worth bothering moving the light to the left seat stay when riding abroad?
Title: Re: Mudguard skills
Post by: Brucey on 14 January, 2019, 07:01:21 pm
I use lights mounted on the seatstays but above the wheel. They might be obscured by flappy clothing and/or might be obscured side-on by your legs as you pedal. In the latter case the light becomes a flashing one, so no big deal. [the extent to which this happens depends on frame design; an old fashioned frame with a horizontal top tube and long seat stays is better here without doubt]. The seat stays are not far apart and the light is offset anyway; I wouldn't bother to move it when I'm riding on the other side of the road but I might angle it differently.

FWIW I think rear lights are of most use at long distance when vehicles are coming up behind; you might well be outside of their (dipped beam) headlight range.  From other angles/distances the driver of  any vehicle with working headlights is more likely to see you because of reflectors etc rather than lights.  Many modern rear lights don't cast a lot of light sideways anyway, but a few do.

cheers
Title: Re: Mudguard skills
Post by: trekker12 on 21 January, 2019, 04:17:29 pm
Also consider multiple lights. My main dynamo light is on one seat stay, there is a second cheap flashing light on the other and a third clipped on the carradice bag. In the event one stops working or the battery dies then I have back up as well as being visible from different angles.

The seat stays and mudguard also have a strip of in 3M red reflective tape running vertically down each.
Title: Re: Mudguard skills
Post by: Crumbling Nick on 22 January, 2019, 05:12:03 pm
Agree the seat stay is better maintenance wise for the rear light, but can you counter my suspicion that there is a "blind point" where a road user (e.g. a car) could be in a position such that they can't see my rear light due to the mudguard or wheel being between them and the light source?
IMNSHO there isn't a simple counter. The lighting regs say simply "Visible to the rear". That's pretty vague, so there would need to be case history to provide a definitive interpretation. IANAL, but I cannot imagine that "only totally obscured in a small region" would be accepted as a defence in court. Obviously, if the light is wide enough that a reasonable amount of it is visble despite the wheel/mudguard you'd have a better defence. However it would be rather vulnerable.

I'm currently engaged in upgrading the lights on youngest daughter's bike, which has a Shimano alternator to power primary lights. I believe that 2 rear lights are esssential for utility cycling. Failures happen, so a backup is needed. Also, flashing lights are probably better at attracting attention, but steady lights help following road users judge distance, apart from being almost a legal reqiurement. My personal opinion is that the 2 lights need to be separated by a significant distance to work effectively. That is based on the problem I have with some modern cars, where rear indicators become overwhelmed by brake lights until too close for anticipatory riding.

The OE rear light is mounted on the rear of the pannier rack & has now been replaced by a better one. The only alternative mounting point which will never be obscured by bags or other cargo on the rack is the mudguard. Even there it's hard to find a place which is reasonably separated, has adequate support to avoid plastic fractures & isn't vulnerable to damage. My own bikes have a light in each location, but even then there are compomises; mudguard mounted dynamo lights have inefficient optics, but flashing lights are heavier & bigger, so are more vulnerable & more likely to cause fatigue failures.
Quote
Is it worth bothering moving the light to the left seat stay when riding abroad?
I don't know. UK lighting regs specify "On the centre-line or off side of the vehicle". I don't think that an alternative that complies with EU regs is allowed, so I'd guess it'is country-specific when you're abroad.
Title: Re: Mudguard skills
Post by: Ben T on 22 January, 2019, 06:07:17 pm
I'm not bothered about the law (as much), I'm mainly bothered about safety.
Title: Re: Mudguard skills
Post by: Kim on 22 January, 2019, 08:08:35 pm
I don't think there's any evidence that rear bicycle lights contribute towards safety, is there?
Title: Re: Mudguard skills
Post by: Ben T on 22 January, 2019, 09:44:49 pm
Not sure about evidence, I certainly think they do.
Title: Re: Mudguard skills
Post by: rogerzilla on 23 January, 2019, 11:31:40 am
Basically, the "unbreakable" SKS guards are a bit shit for anything other than German roads, and the vibration kills them.  The best tip is to avoid the narrowest P35 ones and buy at least P45.  These are stiffer so they take a lot longer to shake themselves to death.  I used to get through P35s in less than a year.
Title: Re: Mudguard skills
Post by: rogerzilla on 23 January, 2019, 11:35:22 am
I don't think there's any evidence that rear bicycle lights contribute towards safety, is there?
Are there any CTC types still alive who resisted rear lights when they were first made legal?  The theory was that drivers should be able to stop within the range of their headlights* and a reflector should be enough...which seems logical, but I wouldn't want to test it with my life.

*if you flick from main to dipped beam at 60mph, your visibility goes from half a mile to 100 yards, just like that
Title: Re: Mudguard skills
Post by: Brucey on 23 January, 2019, 12:27:50 pm
rear lights have always been 'legal', presumably you mean 'compulsory' which is different.  There is plenty of documented discussion on this point and the other major CTC issue of the time, that of dedicated cycle paths, which the CTC were also against for various reasons.

Pedestrians walking on country roads are obliged to carry no lights or reflectors and occupy about the same road space as a bicycle.  However a pedestrian is able to jump into the verge if they have to.

 When riding country roads at night I have always taken note of the way my shadow is cast from car headlights behind. If the shadow is still cast directly forwards as a vehicle draws close that might be the last thing you ever see; just once or twice I have taken evasive action.

cheers
Title: Re: Mudguard skills
Post by: FifeingEejit on 23 January, 2019, 01:43:09 pm
I don't think there's any evidence that rear bicycle lights contribute towards safety, is there?
Are there any CTC types still alive who resisted rear lights when they were first made legal?  The theory was that drivers should be able to stop within the range of their headlights* and a reflector should be enough...which seems logical, but I wouldn't want to test it with my life.

*if you flick from main to dipped beam at 60mph, your visibility goes from half a mile to 100 yards, just like that

Assuming the highway yard of 1m
75m is the highway code stopping distance for 60mph
at 60mph you travel 100m in 3.7 seconds on a dry clean road

So in theory it's sufficient...

However, if you're on an open road and on dipped beams, then chances are you're on dipped beam because there is an oncoming vehicle.
If there's an oncoming vehicle then there is a pair of bright white lights reducing your light sensitivity and just like that other great big bright light that reduces light sensitivity the sun, means there's contrast issues that are going to make it near impossible to see the dim return of light from a reflector.

For all the stealth ninja's I've come across in town while cycling or riding the existence of street lighting has helped make them at least distinct, but the worse I've come across was a dark coloured car on the dual carriageway between Dundee and Perth with no working rear lights and a closing speed around 20mph.

It wasn't the reflectors that gave me a chance of seeing them when I did, it was the light spill from the street lights in Glencarse seen through their rear window giving me the outline of the car.
Title: Re: Mudguard skills
Post by: quixoticgeek on 24 January, 2019, 10:21:30 am
Pedestrians walking on country roads are obliged to carry no lights or reflectors and occupy about the same road space as a bicycle.  However a pedestrian is able to jump into the verge if they have to.

Pedestrians on roads with no footway are supposed to walk on the opposite side of the road, into the direction of oncoming traffic. This makes it possible for the pedestrian to see the oncoming threat.

J

Title: Re: Mudguard skills
Post by: De Sisti on 24 January, 2019, 12:16:05 pm
My rear mudguard snapped just below the bridge of the seat stays. I cut two holes either side
of the split and used zip ties to go through the holes and above the bridge to make a secure
refit.
(https://farm5.staticflickr.com/4911/32984794068_135cb75789_z.jpg)
Title: Re: Mudguard skills
Post by: mattc on 24 January, 2019, 01:34:28 pm
Agree the seat stay is better maintenance wise for the rear light, but can you counter my suspicion that there is a "blind point" where a road user (e.g. a car) could be in a position such that they can't see my rear light due to the mudguard or wheel being between them and the light source?

Is it worth bothering moving the light to the left seat stay when riding abroad?
I would definitely not ride with just a rear light that is obscured by the wheel. The "blind spot" would be when a driver approaches from behind on a long (fast) LH-bend. Just not worth the gamble IMHO.

Likewise, I tend to move lights over to the left for riding in relevant foreign countries.

(I usually have a bag or a rack that I can mount rear lights to. Mudguards are for reflectors, ideally. And for being nice to other cyclists  O:-)  )
Title: Re: Mudguard skills
Post by: grams on 24 January, 2019, 01:48:08 pm
The Portland Design Works mudguards are thick enough to be unlikely to snap like chromoplastics inevitably do, and the spacing of the rear mudguard flap holes is perfect for mounting a mudguard rear light, and they can easily take the weight. Nice telescopic adjustment system too.

Pricey though.

(and they insist on calling them "fenders", whatever they are)
Title: Re: Mudguard skills
Post by: Paul H on 24 January, 2019, 03:05:34 pm
I use rubber tap washers when fitting guards, threadlock the screws and don't over tighten, before finally fitting I loosen everything to check there's no straining.  I'm lucky that my bikes have direct fittings and don't use the guard brackets.  Where possible I also use a Tubus bracket to attach the rear on to a rack. I've yet to break one in normal use, two have broke in accidents and another snapped trying to move it between bikes.  I gave up on dynamo mudguard lights, they just don't survive my usage, I don't think I kept one long enough to test the guard.  The SKS range has changed in recent years, I fitted some Blumel Matt 18 months ago mainly because I liked the look of them, they do feel a bit more pliable than the traditional Chromoplastics, still  looking like new on a bike that gets used most days.
Title: Re: Mudguard skills
Post by: Kim on 24 January, 2019, 03:12:55 pm
(and they insist on calling them "fenders", whatever they are)

Perfectly acceptable for a USAnian company to use the USAnian term for things that were invented between the colonial era and their re-invasion of BRITAIN during WW2.  If it bothers you, just picture them wearing their cacky pants with suspenders.
Title: Re: Mudguard skills
Post by: quixoticgeek on 24 January, 2019, 03:15:47 pm
I don't think there's any evidence that rear bicycle lights contribute towards safety, is there?

Depends what you mean by contribute. Round these parts they are a legal requirement, but many riders have the merest hint of a tiny LED light, somewhere on their body, and as many riders again don't even bother with lights...

Before retroreflectors were common place, Dutch law required the bottom part of your rear mudguard be painted white (effectively making a mudguard a legal requirement...). You can occasionally see an older bike with the white mudguard from this time.

I have 3 rear lights, plus all the reflectivor tape gubbins RATN required last year. On xmas day on my festive 500 attempt, I ended up on a 70kph main road in Germany, in conditions where motorists would not expect a cyclist, after 100m, I stopped and put on a hivi which I had because of France. I object to Hivi's in general, but on that road, in those conditions, I chose to opt for one, along with 3 rear lights, and reflectors... I had a couple of motorists (one BMW, one Audi), beep at me, as they passed fast and close, obviously feeling I shouldn't be there...

Ultimately the lighting I have on the rear is as much for the avoidance of doubt in the event of an accident than anything else. "You couldn't see me? I'm like a bloody xmas tree here!", but I can tailor the amount of it I actually turn on. On Dutch roads, it tends to just be the seat stay mounted dynamo light.

J
Title: Re: Mudguard skills
Post by: Kim on 24 January, 2019, 03:36:20 pm
I don't think there's any evidence that rear bicycle lights contribute towards safety, is there?

Depends what you mean by contribute.

I meant actually preventing collisions with other road users, rather than being a legal requirement or avoiding accusations of contributory negligence.  AIUI what data there is (at least in the UK) is inconclusive, with the rate of KSIs being independent of darkness.

Of course, most cycling collisions happen in urban areas, so perhaps lighting is more beneficial on unlit roads.  There's also the argument that sufficiently obnoxious lights might reduce the looked-but-failed-to-see rate, as per other Theory Of Big factors.

The way I see it, irrespective of any safety benefit, front lights are beneficial for helping you to go faster without crashing into things (which may be subject to risk compensation and therefore not appear in the stats).  On the basis I've got lighting at the front I'm happy to comply with the legal requirement for a rear light too, if only for the contributory negligence angle, and in doing so I might as well make an effort to have a decent one.  Reflectors are like rear lights but lighter and lower maintenance - so you might as well have them - and drifting back on topic - rear mudguards are a good place to put one.


Quote
On xmas day on my festive 500 attempt, I ended up on a 70kph main road in Germany, in conditions where motorists would not expect a cyclist, after 100m, I stopped and put on a hivi which I had because of France. I object to Hivi's in general, but on that road, in those conditions, I chose to opt for one

I'm not a fan of it either (I'm happy to dress the bike up like something from Tron, but I don't want to look like a railway worker just to ride a bike).  I have donned a yellow Altura-alike for its hi-vis (rather than weather-protective) properties on a couple of occasions, chiefly during dense fog in daylight, and when directing traffic at the scene of an accident.


Quote
Ultimately the lighting I have on the rear is as much for the avoidance of doubt in the event of an accident than anything else. "You couldn't see me? I'm like a bloody xmas tree here!", but I can tailor the amount of it I actually turn on. On Dutch roads, it tends to just be the seat stay mounted dynamo light.

Agreed.  I've got the B&M dynamo light for normal riding (particularly in groups) and the obnoxious blinky for scary roads and really foul weather.  I have been known to adorn my bicycle with actual christmas lights, but that didn't stop an impatient Brummie trying to drive their car at me.
Title: Re: Mudguard skills
Post by: De Sisti on 24 January, 2019, 03:44:45 pm
,,,,, I ended up on a 70kph main road in Germany, in conditions where motorists would not expect a cyclist,

Apart from autobahns, what other roads in Germany would motorists not expect to see a cyclist?

,,, I had a couple of motorists (one BMW, one Audi), beep at me,

Audis and BMWs in Germany?
Title: Re: Mudguard skills
Post by: Jakob W on 24 January, 2019, 03:55:52 pm
IIRC in Germany (as in NL) it's compulsory to use a cycleway if there is one alongside the main road (subject to certain caveats, which the motons tend to be unaware of, so if you ride in the road they'll beep at you regardless...)
Title: Re: Mudguard skills
Post by: De Sisti on 24 January, 2019, 04:10:15 pm
IIRC in Germany (as in NL) it's compulsory to use a cycleway if there is one alongside the main road (subject to certain caveats, which the motons tend to be unaware of, so if you ride in the road they'll beep at you regardless...)
Is there an exemption for professional cyclists (if they're not training abroad)?
Title: Re: Mudguard skills
Post by: Kim on 24 January, 2019, 04:19:43 pm
IIRC in Germany (as in NL) it's compulsory to use a cycleway if there is one alongside the main road (subject to certain caveats, which the motons tend to be unaware of, so if you ride in the road they'll beep at you regardless...)
Is there an exemption for professional cyclists (if they're not training abroad)?

AIUI the German rule depends on whether the cyclepath is signposted or not - without the blue sign, it's not compulsory to use it.

IIRC there's an exemption for when you've got more than n cyclists riding in a tight group.  Also for cycles over a certain width, and for when the cyclepath is obstructed by roadworks.  Probably some other things.  Paging Auntie Helen.  Auntie Helen to the Höflichkeitstelefon, please...
Title: Re: Mudguard skills
Post by: mrcharly-YHT on 24 January, 2019, 04:27:24 pm
I have come very, very close (by a bum squeak) to crashing into someone who didn't have rear lights. Several occasions. These are when I was cycling, my lights pointing at road and ahead, I was travelling fast, they were moving slowly, in dark clothing and weaving a bit. Didn't see them until very very close.

Not had same experience with people who had red lights on their bike.

Based on that, I think red rear lights assist safety on the road.
Title: Re: Mudguard skills
Post by: Kim on 24 January, 2019, 06:22:01 pm
I have come very, very close (by a bum squeak) to crashing into someone who didn't have rear lights. Several occasions. These are when I was cycling, my lights pointing at road and ahead, I was travelling fast, they were moving slowly, in dark clothing and weaving a bit. Didn't see them until very very close.

Not had same experience with people who had red lights on their bike.

Based on that, I think red rear lights assist safety on the road.

And of course Bike vs Bike collisions are likely to not appear (or be misreported) in the stats...
Title: Re: Mudguard skills
Post by: Brucey on 24 January, 2019, 06:38:59 pm
some fenders

(http://thumbs4.ebaystatic.com/d/l800/pict/262329112749_1.jpg)

Title: Re: Mudguard skills
Post by: Cudzoziemiec on 24 January, 2019, 06:59:36 pm
Pedestrians walking on country roads are obliged to carry no lights or reflectors and occupy about the same road space as a bicycle.  However a pedestrian is able to jump into the verge if they have to.

Pedestrians on roads with no footway are supposed to walk on the opposite side of the road, into the direction of oncoming traffic. This makes it possible for the pedestrian to see the oncoming threat.

J
In Poland (and possibly other countries) pedestrians are required by law to wear hivis, after dark outside built-up areas. Although there aren't any fines or other legal penalties for not complying, presumably it could be held to be a contributory factor in a collision. I've also seen many pedestrians doing the same in UK, though there's no talk of it becoming compulsory.
Title: Re: Mudguard skills
Post by: FifeingEejit on 24 January, 2019, 07:17:01 pm
some fenders

(http://thumbs4.ebaystatic.com/d/l800/pict/262329112749_1.jpg)

I was going to say "Fenders" are "Bumpers" not mudguards but that covers it better!


When it comes to the reflectors being enough to be seen by thing...

I was pondering it on the way home the other night.
My normal commute in the cars (I have access to a "few") involves driving through town where the lighting is about 10m apart, onto a bridge where it's about the same, into the unlit darkness on a dual carriageway, round a roundabout that's lit and then onto a wide open single carriageway before descending to another normally lit roundabout and then into the darkness of woods on a twisty lumpy road before reappearing into the relative lightness of a village with street lights about 25m apart and white Led or Tube sources.

What grabbed my attention was the variation in how far the light beam extended.
In town I've mentioned the stealth ninjas before so leave it at that.
Once over the bridge the Dual Carriageway climbs, the direct light was only about 10m ahead of me, but the spill was able to cause the signs at that section to be visible (they are surprisingly clean signs)
At the top of the climb it was maybe 25m and I could see all the signs down to the lit roundabout, that leads onto the single carriageway road.
Again likewise on the good visibility of the single carriageway that's all down hill.

However on the narrow twisty road through the woods, the short climbs would be enough to take any reflector out of the light spill area, likewise on the curves where you can see tail lights.

Then in the village I spotted something with a neighbours car, it has two very low red reflectors on the lower rear bodywork well below bumper bar level.
Quite worryingly despite the road being flat they returned my headlights only when there was direct illumination from about 10m.

So my suspicion from that is that the visibility created by a rear reflector returning the light emitted from a following vehicle is dependent on:
The height of the reflector
The height and aim of the light expected to light it up
The road profile.
And therefore as the light beam arrives from below on the flat, it's probably better to have a reflector low down than high up.

I'm tempted to take the car and bike along to the flattest, straightest, darkest, quietest road round here and try out some tests.

Then I looked at a photo I took on Yorkshire Grit, just before sunset of a trike with two Cateye lights at rear axle level flashing away, maybe 1km away up the top of a rise.
I could see the lights at that distance where there was no way a headlight would ever reach the reflectors.
THere's also a few more:

https://1drv.ms/u/s!AlB7bV6RdTovhso1LbKI0b28p52L6Q
I had my light on all day, you can see two rear lights in this one, one near and one far away, can't tell if the bike in front of me had a reflector.

https://1drv.ms/u/s!AlB7bV6RdTovhsokkpmOvTqyl2a_Wg
The trike quite a way ahead, but there's a red glow in the picture


Also something to remember is only a few weeks ago a fatal accident was directly attributed to the rear reflector being the only and inadequate warning of presences on a dark country road.

As for pedestrians; I'm sure there's something in the Highway code about groups carrying a torch at the front and a red position lamp at the back, but nothing for individual pedestrians. Though walking along country roads in the dark without a torch is a rather interesting challenge if there isn't any ambient light any way...
Title: Re: Mudguard skills
Post by: Jakob W on 24 January, 2019, 09:09:19 pm
some fenders

(http://thumbs4.ebaystatic.com/d/l800/pict/262329112749_1.jpg)

More Fenders:
(http://www.strat-talk.com/data/attachments/226/226080-a5d2da3bab90768b586a07fa12558905.jpg)
Title: Re: Mudguard skills
Post by: Cudzoziemiec on 24 January, 2019, 09:16:17 pm
As for pedestrians; I'm sure there's something in the Highway code about groups carrying a torch at the front and a red position lamp at the back, but nothing for individual pedestrians. Though walking along country roads in the dark without a torch is a rather interesting challenge if there isn't any ambient light any way...
Yeah, there's something about pedestrians in organised groups or columns carrying lights. I think it's advisory rather than compulsory though. I'm not sure if it sets out a minimum size at which it begins to be relevant.
Title: Re: Mudguard skills
Post by: Crumbling Nick on 24 January, 2019, 10:35:27 pm
I'm not bothered about the law (as much), I'm mainly bothered about safety.
Ben,
After what has been posted after that brief comment, I think you'll have a glimmering of an idea of why I started from a legalistic approach. There is much wisdom in UK laws, just as the Highway Code is intended to be a guide to best practice. By & large that's the same as safety, despite the unimaginative bits e.g. the stupidity of the pedal reflector regs. which AIUI mean that it's illegal to ride a recumbent bike at night {obviously not what Parliament intended when delegating authority for the regs. in 1989}.

I'll come back to a more specific reply to your original post; we share similar problems, and some of my experience may be relevant & vice versa. btw which bits of abroad were you thinking about?

Meanwhile I must thank Brucey for his first response. There is a lot of considered wisdom/experience in that post. I learnt much from it, which prompted some thoughts of my own which I shall add to the discussion in due course.
Title: Re: Mudguard skills
Post by: Brucey on 24 January, 2019, 10:38:41 pm
re reflectors; they only work if the included angle between the light source and the viewer is small.  This means that they work very well for a typical car driver over a wide range of distances, because they are basically peering over the top of their headlights.  However they work less well (at short distances especially) for some cyclists who have their front light mounted low down.

The legally mandated reflectors fitted on vehicles are all prismatic type.  Reflexite tapes are either beaded type or prismatic type. There is a write-up here

http://reflectivetape.info/what-is-the-difference-between-glass-bead-and-prismatic-reflective-tape/ (http://reflectivetape.info/what-is-the-difference-between-glass-bead-and-prismatic-reflective-tape/)

which explains the difference between them but basically, prismatic reflectors reflect more efficiently but over a smaller angle.  In terms of brightness the reflection varies by a factor of about x13 which translates to an angle variation of about x3.5 (assuming the overall efficiency is about constant). IIRC the smallest viewing angle is about 0.5 degrees off-axis.

So if you are a height 'h' away from your light source  anything that is at least ~(115 h) away from you will present at one degree or less and will light up if it is retroreflective. Any closer and it may not;  however if it is a wide angle retroreflective (less bright, wider angle)  then the minimum distance is ~33h.

So with any 'dipped beam' arrangement you are potentially  in trouble if you don't project enough light to see by directly to about the same distance as the minimum distance that you will expect to see a retroreflector by. 

In terms of cycling there are a few things to take away;

1) when cycling you are unlikely to spot prismatic reflectors other vehicles at close distances using a short-range bike light, set low,  with a sharp cutoff; those reflectors are not meant for you to see that way.

2) if you want to be seen at great distance then carrying high-efficiency low angle prismatic type retroreflectives is a very good idea.

3) if you want to be seen at much shorter distances then carrying high angle beaded retroreflectives is a really good idea; typically these light up (from a car driver's perspective ) very strongly within the range of their dipped beams and this might make the difference between a collision and not.

4) There is enough 'spill' from most car lights to allow retroreflectives to be clearly visible even when they are above the cutoff of the dipped beam; however this is the first thing that wil be lost to a viewer whenever there is any dazzle.

cheers
Title: Re: Mudguard skills
Post by: grams on 24 January, 2019, 10:44:35 pm
I have come very, very close (by a bum squeak) to crashing into someone who didn't have rear lights. Several occasions. These are when I was cycling, my lights pointing at road and ahead, I was travelling fast, they were moving slowly, in dark clothing and weaving a bit. Didn't see them until very very close.

As no one was harmed, the evidence above points to riding without lights having *exactly* the same injury rate as riding with them.

In London at least, maybe half the cyclists on the road at night have either no rear light or a light so feeble that (when driving) you've seen their silhouette and/or their pedal reflectors flashing long before you can see whatever red light is emanating from the dead watch battery on their seatpost. And yet cyclists being hit from behind at night doesn't seem to be A Thing.
Title: Re: Mudguard skills
Post by: Kim on 24 January, 2019, 10:47:07 pm
I was going to say "Fenders" are "Bumpers" not mudguards but that covers it better!

Surely bumpers are bumpers and fenders are wings?
Title: Re: Mudguard skills
Post by: Ben T on 24 January, 2019, 11:12:55 pm
I'm not bothered about the law (as much), I'm mainly bothered about safety.
Ben,
After what has been posted after that brief comment, I think you'll have a glimmering of an idea of why I started from a legalistic approach. There is much wisdom in UK laws, just as the Highway Code is intended to be a guide to best practice. By & large that's the same as safety, despite the unimaginative bits e.g. the stupidity of the pedal reflector regs. which AIUI mean that it's illegal to ride a recumbent bike at night {obviously not what Parliament intended when delegating authority for the regs. in 1989}.

I'll come back to a more specific reply to your original post; we share similar problems, and some of my experience may be relevant & vice versa. btw which bits of abroad were you thinking about?

Meanwhile I must thank Brucey for his first response. There is a lot of considered wisdom/experience in that post. I learnt much from it, which prompted some thoughts of my own which I shall add to the discussion in due course.

Yes I guess the law is often largely the same as safety. My thinking was that safety is over and above the law, ie you can be legal, but I want to also be safe on top of that.
I was thinking mainly France but also USA.
Title: Re: Mudguard skills
Post by: quixoticgeek on 24 January, 2019, 11:49:04 pm

I meant actually preventing collisions with other road users, rather than being a legal requirement or avoiding accusations of contributory negligence.  AIUI what data there is (at least in the UK) is inconclusive, with the rate of KSIs being independent of darkness.

It's a hard one to test for. I wonder what data is available?

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The way I see it, irrespective of any safety benefit, front lights are beneficial for helping you to go faster without crashing into things (which may be subject to risk compensation and therefore not appear in the stats).  On the basis I've got lighting at the front I'm happy to comply with the legal requirement for a rear light too, if only for the contributory negligence angle, and in doing so I might as well make an effort to have a decent one.  Reflectors are like rear lights but lighter and lower maintenance - so you might as well have them - and drifting back on topic - rear mudguards are a good place to put one.

I only use a mudguard if I don't have my saddle bag on there. It's one of the bike packing style, so acts as a pretty good thing for keeping the mud and water off my arse. Mudguards drive me nuts, they rattle, they get blown around in cross winds, and they eventually self destruct... Adding a weight to them seems... sub optimal.

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I'm not a fan of it either (I'm happy to dress the bike up like something from Tron, but I don't want to look like a railway worker just to ride a bike).  I have donned a yellow Altura-alike for its hi-vis (rather than weather-protective) properties on a couple of occasions, chiefly during dense fog in daylight, and when directing traffic at the scene of an accident.

Yeah, I'm much happier with policies around the bike being lit up, covered in reflecty stuff etc..., rather than the rider.

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Agreed.  I've got the B&M dynamo light for normal riding (particularly in groups) and the obnoxious blinky for scary roads and really foul weather.  I have been known to adorn my bicycle with actual christmas lights, but that didn't stop an impatient Brummie trying to drive their car at me.

Would anything? I have a B&M Secular Dynamo on the left, Secular Perminant on the right, and a cat eye with built in reflector on the seat post.

Apart from autobahns, what other roads in Germany would motorists not expect to see a cyclist?

Being legally allowed to cycle there, vs expecting a bike to be there are two separate things. You can legally cycle down the A14, I wouldn't expect anyone to be that crazy... At 8pm, on Xmas day, in the middle of nowhere on a 70kph road, a cyclist is not something you really expect...

AIUI the German rule depends on whether the cyclepath is signposted or not - without the blue sign, it's not compulsory to use it.

Correct, and because of the extra maintenance requirements of having the blue sign there, and it being an official bike path, many local authorities have removed the blue bike sign from the cycle path that goes along side a road, making it optional. Mandatory or not, many drivers think you should be using it, I've had many drivers slow down and shout stuff at me through open windows when cycling on German roads. I had one driver slow down to tell me I should be cycling on the road the other side of the armco barrier, neglecting to realise that I'd quite like to be there, but there hasn't be a way for me to get over the armco, and across the ditch between me and said road for the last 5km, otherwise I would... On the xmas day example listed above, there was no cycle path along the road. If there was, I'd have used it.

In Belgium recently I had a lot of people beeping at me and shouting at me for not using the cycle path, ignorant to the fact that the cycle path was basically a sheet of ice, and thus it was too dangerous to cycle there (I did try). Other times it's been too pot holed, too full of broken glass, etc... And yet still entitled wankers in metal death boxes shout and beep and hurl abuse.

Drivers never seem to think about the reason the cyclist might choose to dice with death in the main road, rather than use the cycle path. Could it be because this is the safer choice?

I have come very, very close (by a bum squeak) to crashing into someone who didn't have rear lights. Several occasions. These are when I was cycling, my lights pointing at road and ahead, I was travelling fast, they were moving slowly, in dark clothing and weaving a bit. Didn't see them until very very close.

Not had same experience with people who had red lights on their bike.

Based on that, I think red rear lights assist safety on the road.

I've had this when cycling in Amsterdam. Random stealth cyclists decloak out of nowhere, dressed all in black and with no lights. You get used to it...

One thing I find infuriating is the people who don't understand that fluorescent clothing doesn't work in the dark. One evening cycling through Vondelpark I saw a dark void, with a very tiny green LED glow in entirely the wrong place. I slowed down, and as I got closer, the 2 police horses became visible in the gloom. They had fluorescent stuff on them to make them visible in sunlight, but in the dark, it did nothing. The only indication it was there was the Power LED of their radios. It's a shared use path, you expect tourists, zombies, drunks, morons, kamikaze stealth cyclists, and occasionally all of the above as one unit. But that was the first time I'd seen horses there... I've added them to the things to expect when cycling home from the office...

In Poland (and possibly other countries) pedestrians are required by law to wear hivis, after dark outside built-up areas. Although there aren't any fines or other legal penalties for not complying, presumably it could be held to be a contributory factor in a collision. I've also seen many pedestrians doing the same in UK, though there's no talk of it becoming compulsory.

Ditto Finland, and I believe one of the Baltic states (can't remember which one). Personally I feel that having to wear a hivi vest to use the roads, is a bit like mandating bullet proof vests to prevent shooting deaths in countries with poor gun control. It would be better for those in the position of power aka the drivers, slowed down a bit, and gave more space to other road uses. It would also be better if the roads were designed with this in mind. Walking home from the pub shouldn't require me to dress like I'm working on a railway line...


When it comes to the reflectors being enough to be seen by thing...

So my suspicion from that is that the visibility created by a rear reflector returning the light emitted from a following vehicle is dependent on:
The height of the reflector
The height and aim of the light expected to light it up
The road profile.
And therefore as the light beam arrives from below on the flat, it's probably better to have a reflector low down than high up.

The best reflector for being seen by is the one on the pedals, because it moves. The rear reflector is just yet another red dot in the sea of lights.

I'm very impressed by the reflective properties of the side wall reflectors on tyres. I wish they were available on more tyres. Conti seems to not do them on their GP 4 Seasons, but do on their GP4000s ii (and not on their GP5000...)

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I'm tempted to take the car and bike along to the flattest, straightest, darkest, quietest road round here and try out some tests.

I'd be interested in your results.

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Then I looked at a photo I took on Yorkshire Grit, just before sunset of a trike with two Cateye lights at rear axle level flashing away, maybe 1km away up the top of a rise.
I could see the lights at that distance where there was no way a headlight would ever reach the reflectors.
THere's also a few more:

https://1drv.ms/u/s!AlB7bV6RdTovhso1LbKI0b28p52L6Q
I had my light on all day, you can see two rear lights in this one, one near and one far away, can't tell if the bike in front of me had a reflector.

First thing I notice in that picture is the white reflective bits on the calf of the riders tights...

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Also something to remember is only a few weeks ago a fatal accident was directly attributed to the rear reflector being the only and inadequate warning of presences on a dark country road.

Not the driver going perhaps faster than necessary? not paying enough attention?

At the inquest of Mike Hall, they tried to suggest the height of Mikes rear light was too close to the height of the reflectors on the side of the road, obscuring him...

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As for pedestrians; I'm sure there's something in the Highway code about groups carrying a torch at the front and a red position lamp at the back, but nothing for individual pedestrians. Though walking along country roads in the dark without a torch is a rather interesting challenge if there isn't any ambient light any way...

You'd be surprised, Human night vision is surprisingly good, once you let it adjust. Unfortunately it gets completely buggered the moment some wanker comes round the corner on main beam and blinds you all...

In terms of cycling there are a few things to take away;

1) when cycling you are unlikely to spot prismatic reflectors other vehicles at close distances using a short-range bike light, set low,  with a sharp cutoff; those reflectors are not meant for you to see that way.

2) if you want to be seen at great distance then carrying high-efficiency low angle prismatic type retroreflectives is a very good idea.

3) if you want to be seen at much shorter distances then carrying high angle beaded retroreflectives is a really good idea; typically these light up (from a car driver's perspective ) very strongly within the range of their dipped beams and this might make the difference between a collision and not.

So if you want the best of both worlds, the prismatic reflector that is typically built into bike lights, or sold as bike reflectors, coupled with the glass bead reflective tape that you can get, provides you with long and short range respectively?

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4) There is enough 'spill' from most car lights to allow retroreflectives to be clearly visible even when they are above the cutoff of the dipped beam; however this is the first thing that wil be lost to a viewer whenever there is any dazzle.

There is certainly enough spill on my Edelux II to light up reflective road signs and road markings considerably beyond the reach of what would normally be considered the beam of the light... which can make things... interesting...

Cycling through Flevopolder the other day I saw a weird shape of reflector a few hundred meters up the road, I couldn't work out what it was, it didn't look right for being a sign, or for being a marker post. and it wasn't really moving... Then as I got close it did move, as did it's friend, and their friend, and a couple of other deer... Their eyes make very weird reflectors... and having half a dozen deer charging across the road at you when you're trying to navigate in the dark between the ice patches is... an interesting experience... Turning the next corner and finding the road was a sheet of Ice, I turned round and went to find the nearest station...

Yes I guess the law is often largely the same as safety. My thinking was that safety is over and above the law, ie you can be legal, but I want to also be safe on top of that.
I was thinking mainly France but also USA.

Oh you'd be surprised. Just because it's the law, doesn't mean it's the safest option... See discussion of blinky lights...

Dutch law says you're allowed 1 light at the front, and 1 at the back, no more, not less! You can have more reflectors, but they have to be red to the rear, white to the front, and orange to the side. You'll never get done by the police for having a few lights in each direction, as long as you're not taking the piss, but technically, they could... But then if you actually read the law, most Dutch bikes could incur a fine for something.

In London at least, maybe half the cyclists on the road at night have either no rear light or a light so feeble that (when driving) you've seen their silhouette and/or their pedal reflectors flashing long before you can see whatever red light is emanating from the dead watch battery on their seatpost. And yet cyclists being hit from behind at night doesn't seem to be A Thing.

It's an urban vs rural thing I think. In an urban area the shape/shadow of the cyclist with all the street lights can be enough to make a cyclist visible to the usually slower speeds of the motorists. On country lanes and main roads, drivers don't expect cyclists, so aren't looking for them so if you don't have lights, they may not see you before hitting you. I believe that some of the ultra racers that have been hit by cars when racing have been hit from behind. The solution here is of course for the motorists to slow the fuck down and pay more attention... but hey...

J
Title: Re: Mudguard skills
Post by: Kim on 25 January, 2019, 12:29:03 am
Reflectors are like rear lights but lighter and lower maintenance - so you might as well have them - and drifting back on topic - rear mudguards are a good place to put one.

I only use a mudguard if I don't have my saddle bag on there. It's one of the bike packing style, so acts as a pretty good thing for keeping the mud and water off my arse. Mudguards drive me nuts, they rattle, they get blown around in cross winds, and they eventually self destruct... Adding a weight to them seems... sub optimal.

I've never had much trouble with mudguards (I've been following the discussion of SKS breakages with general bemusement), unless you count the time I hit a pothole and my shitty pannier jumped ship and folded the rear one in half[1] against the tyre.  Or the time I visited .nl and the resulting rattlefest meant I needed to dig out my emergency M6 nylock by lunch time...

I reckon the best reflector for a mudguard is a strip of Scotchlite tape[2], but a dedicated reflector (rather than a light, and certainly not a battery powered one) doesn't weigh much.

(Not that I follow this advice:  My rear mudguards are full of stickers saying things like "Audax UK" and "Bollocks to Brexit".  But then not being a believer in this bikepacking fad[3] my bikes have perfectly good rear racks, with primary lights that incorporate a generous reflector mounted solidly - and permanently correctly aligned - in the obvious place.  Auxiliary blinkies bodged onto the bike frame or rack stays where space and random unused braze-ons permit.)


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First thing I notice in that picture is the white reflective bits on the calf of the riders tights...

Agreed, and that tallies with my real-world experience, which I've generally attributed to my poor sensitivity to red light.  The most astoundingly visible cyclist I've encountered was slowly catching up with Gerwinium OTP riding his Dahon on the Dun Run some years ago.  The combination of the pedalling motion, Altura Night Vision tights and his stereotypical Dutch proportions made him impossible to miss.


[1] It got better.
[2] Particularly given the comment above about the advantages of prismatic vs beaded retroreflectors in different conditions.
[3] I accept that it's the best approach for off-roading or endurance racing, but I'm sarcastically waiting for the cycling industry to decide that panniers are cool again...
Title: Re: Mudguard skills
Post by: Brucey on 25 January, 2019, 01:49:53 am
re reflections from animal eyes; cat's eyes are not named by accident. Before moulded plastic prismatic  retroreflectives were commonly available (1940s?) mostly reflectors on vehicles were glass, and usually based on the same principle as cat's eyes.

Beaded retroreflectives made by 3M are tradenamed 'scotchlite'. One of the less well-known applications of this is in 'front projection' cinematic filming, in which a scene projected from the front falls on both a background screen (made of scotchlite) and the actors etc in the foreground of a shot. The latter  things are so much less reflective that you don't see the reflections from the front projection except under very unusual circumstances.   One of the earliest movies to be shot using front projection was "2001 a space odyssey" and in the opening scenes  you can see the reflection of the front projection in the leopard's eyes. Kubrick was praised for this 'effect' but it was quite accidental and just got left in the film.

cheers
Title: Re: Mudguard skills
Post by: Cudzoziemiec on 25 January, 2019, 09:49:06 am

In Poland (and possibly other countries) pedestrians are required by law to wear hivis, after dark outside built-up areas. Although there aren't any fines or other legal penalties for not complying, presumably it could be held to be a contributory factor in a collision. I've also seen many pedestrians doing the same in UK, though there's no talk of it becoming compulsory.

Ditto Finland, and I believe one of the Baltic states (can't remember which one). Personally I feel that having to wear a hivi vest to use the roads, is a bit like mandating bullet proof vests to prevent shooting deaths in countries with poor gun control. It would be better for those in the position of power aka the drivers, slowed down a bit, and gave more space to other road uses. It would also be better if the roads were designed with this in mind. Walking home from the pub shouldn't require me to dress like I'm working on a railway line...
I agree with all that, but in the case of Poland there are (as everywhere) several factors going on: the obvious and universal tendency to excuse motorists and make others take actions for their mistakes is compounded by the massive increase in car ownership and driving that started in the late 90s, leading to roads full of inexperienced but reckless drivers, and this happens on top of the Soviet bloc inheritance of building for the glorious motoring that didn't happen (so you have a combination of massive arterial roads, once empty now jammed, and horse cart era lanes, not much in between). Polish drivers are curiously respectful around cyclists though, in contrast to the way they treat pedestrians and other drivers. And they give out hiviz in schools.
Title: Re: Mudguard skills
Post by: Ben T on 25 January, 2019, 03:50:19 pm
The Portland Design Works mudguards are thick enough to be unlikely to snap like chromoplastics inevitably do, and the spacing of the rear mudguard flap holes is perfect for mounting a mudguard rear light, and they can easily take the weight. Nice telescopic adjustment system too.

Pricey though.

(and they insist on calling them "fenders", whatever they are)

Have you got any PDW ones? If so can you confirm how accurate the measurements are, i.e. are they actually 30/45mm.
Thinking about possibly getting some but not sure whether to go for 30 or 45mm for 28mm tyres.
Title: Re: Mudguard skills
Post by: grams on 25 January, 2019, 06:15:45 pm
Have you got any PDW ones? If so can you confirm how accurate the measurements are, i.e. are they actually 30/45mm.
Thinking about possibly getting some but not sure whether to go for 30 or 45mm for 28mm tyres.

I have the 30mm ones. They measure 29.5mm wide. I use them with 28mm Gatorskins and they're about the same width.
Title: Re: Mudguard skills
Post by: Cudzoziemiec on 02 February, 2019, 03:11:41 pm
Going back to the question of whether lights are a safety factor: Last week I looked-but-failed-to-see two cyclists. Both happened when I was crossing the road on foot. The first one was early dusk, I looked to the right and saw a car with headlights on but failed to notice the cyclist in front, also with lights. This was partly because the bike lights were in line with but outshone by the car lights behind, and partly because the cyclist was so near the kerb (almost on the yellow lines). The second one was in daylight. I was crossing the right-hand horizontal arm of a T-junction with traffic lights. I'd crossed on the green man to the central island and was looking over my shoulder for a gap in the traffic coming from the vertical arm. Spotted gap, crossed and only then did I see the cyclist who had skipped the lights (possibly by using the pelican – there is a cycle route that comes down another arm of the junction [it's effectively a T-junction with four arms] and dumps you at a pelican with nowhere logical to go) and was coming from the left-hand horizontal arm. I would conclude from this mighty sample that being where people expect to look is the key to getting seen. Whether being seen is the key to not being hit, I will leave for the reader.