Author Topic: reflections from gear/brake cables (Read 2939 times)

mrcharly-YHT · « **on:** 29 January, 2019, 06:35:29 pm »

My cable outers are a grey and *really* reflect my lights. Massive glare.

Don't have anywhere else sensible to mount the lights (currently on handlebars).

Wondered about painting the cable outers with something suitably dull and none-reflective, not sure what would be; a) easy to find, b) durable enough, c) stick to cable outer.

Anyone else solved this already?

Brucey · « **Reply #1 on:** 29 January, 2019, 06:43:31 pm »

the intensity of you lights will drop off with distance as ~ 1/r^2 (depending on how the beam is configured). You want to be looking at stuff that is (say) 10m away which is illuminated by the same light as you are projecting on your cables which are (say) 0.1m away. You don't need to be a genius to work out that if you want your cables to be as bright as the things you want to be looking at, they need to be about 1/1000000 as reflective.

The sensible solution to this is not to point your lights at your cables. It shouldn't be too difficult to arrange this by moving one or the other.

cheers

Jurek · « **Reply #2 on:** 29 January, 2019, 06:44:04 pm »

I used to have this on the FNRTTCs.
My solution to it was to cable tie the outers so that they were pulled away from the direct beam of my Hopes.
Not ideal (or attractive) as a cable run, but seemed to solve the issue, and gears and brakes still worked.
I guess it depends on how much leeway / pull you need to apply to the outers.

ETA - you need to be a bit creative as to where you apply the cable ties. For me what worked was gathering the outers with a cable ties - 'woggle stylee' - if you will - effectively making the arc of their run, a tighter radius.

Cudzoziemiec · « **Reply #3 on:** 29 January, 2019, 06:52:18 pm »

I used to have the same problem with black cable outers, so I don't think that's going to be a successful route. I solved it by going dynamo and moving the headlight to the fork crown. Some battery lights can be fixed there too, but I'm not sure which ones. Probably Jurek's suggestion of moving the cables away from the light beam is most practical.

Kim · « **Reply #4 on:** 29 January, 2019, 07:14:34 pm »

Black wrap (a sort of light-absorbing aluminium tape used in the entertainment industry) if you can scrounge a bit of it. Or a black cloth-effect bar tape. Possibly you might have better results trying to shield your eyes from the reflected light than reducing the amount of light reflected - I'm imagining some sort of hood for the light.

But getting the cables out of the beam would be my preferred approach, for obvious reasons. I have this problem on my mountain bike, with the front brake hose (standard not particularly shiny black colour) getting in front of the only suitable bit of handlebar for mounting a light. I ride that so little in darkness that I consider it a mild irritation. My other bikes have fork crown and boom mounted lights, which avoid the problem (though foot flash^[1] is a spiritual relative). Perhaps use a SpaceGrip or similar to move the light further forward?

_{[1] On which note, mounting the light further forward of the bottom bracket shell is a better way to reduce foot flash than eg. wearing dark-coloured shoes. The rookie mistake is to mount the light somewhere directly above the bottom bracket in the interests of height.}

Cudzoziemiec · « **Reply #5 on:** 29 January, 2019, 08:19:37 pm »

If the reflections are coming from the cables, how would a hood on the light help? Surely it would have to be on the cables (which would probably introduce all sorts of weird artefacts and shadows).

Kim · « **Reply #6 on:** 29 January, 2019, 08:21:19 pm »

Quote from: Cudzoziemiec on 29 January, 2019, 08:19:37 pm

If the reflections are coming from the cables, how would a hood on the light help? Surely it would have to be on the cables (which would probably introduce all sorts of weird artefacts and shadows).

In ASCII art terms:

eye<

hood-------------
light< cable

Cudzoziemiec · « **Reply #7 on:** 29 January, 2019, 08:24:41 pm »

Well if it can be made that long it might work, dependent on relative heights of light and cables.

Kim · « **Reply #8 on:** 29 January, 2019, 08:28:26 pm »

Yeah. Would work okay on my MTB, where the hose is about 50mm in front of the light. Might be completely impractical on drops...

rogerzilla · « **Reply #9 on:** 29 January, 2019, 08:43:18 pm »

You need some of that super-black paint that Anish Kapoor uses.

rafletcher · « **Reply #10 on:** 29 January, 2019, 08:46:48 pm »

As Kim mentioned, cloth tape would do the job. Like old insulation tape, or old style bar tape.

Brucey · « **Reply #11 on:** 29 January, 2019, 08:57:51 pm »

Quote from: rafletcher on 29 January, 2019, 08:46:48 pm

As Kim mentioned, cloth tape would do the job. Like old insulation tape, or old style bar tape.

only if it is about a million times less reflective than the stuff you want to see about ten metres away when it is illuminated by the light.

Hence my earlier suggestion that you shouldn't point the light at the cables and should move one or the other. The hood idea would work too.

cheers

hubner · « **Reply #12 on:** 29 January, 2019, 09:23:46 pm »

I guess this problem is only caused by Shimano STI levers where the gear cables emerge horizontally and goes right in front of the bar tops.

OK, drastic problems need drastic solutions:
Switch to Campagnolo where both gear and brake cables go under the tape.
Used non-aero brake levers (what I use).

Kim · « **Reply #13 on:** 29 January, 2019, 09:28:20 pm »

Quote from: hubner on 29 January, 2019, 09:23:46 pm

I guess this problem is only caused by Shimano STI levers where the gear cables emerge horizontally and goes right in front of the bar tops.

No, it's caused by mounting lights on the handlebars.

Cudzoziemiec · « **Reply #14 on:** 29 January, 2019, 09:39:53 pm »

Also, mr_charly hasn't said whether this is a drop bar or straight bar bike, which affects the bar-rerouting potential.

freeflow · « **Reply #15 on:** 29 January, 2019, 11:22:08 pm »

Use an extension bracket which will move the lights ahead of the cables.

mrcharly-YHT · « **Reply #16 on:** 29 January, 2019, 11:38:26 pm »

Kim and hubner are correct. The light is a cateye, with the latest cateye mount; a lacky band that only really works round the handlebars.

I also get reflections off the front rack.
Cloth tape sounds a good idea. Occurs to me that warhammer black might work

Brucey · « **Reply #17 on:** 29 January, 2019, 11:43:48 pm »

If you have a front rack, just attach a short length of 7/8" broom handle to it, (or a cork, or W.H.Y.) and mount the light on that.

cheers

Kim · « **Reply #18 on:** 29 January, 2019, 11:46:25 pm »

Cover the cable in flawless retroreflectors and direct the light back to the source.

Or use an invisible cable...

Wait, this is an excuse for DI2 and/or dynamo lighting.

fuaran · « **Reply #19 on:** 30 January, 2019, 01:10:49 am »

Quote from: hubner on 29 January, 2019, 09:23:46 pm

I guess this problem is only caused by Shimano STI levers where the gear cables emerge horizontally and goes right in front of the bar tops.

Just about any of the newer STI levers have the cables under the tape. Even Sora does, for a couple of years now.

If you cover the cables with something non-reflective, you could still get annoying shadow patterns on the road.
Best to get the lights in front of the cables where possible. You can bend the cables back a bit, with a few zip ties to hold them in place. So long as it doesn't cause any sharp angles.

Deano · « **Reply #20 on:** 30 January, 2019, 08:01:08 am »

Ride fixed - no need for gear cables.

trekker12 · « **Reply #21 on:** 30 January, 2019, 01:25:48 pm »

Or 1x10, or 1x9, or whatever is easiest on your bike as I'm assuming it's an older gearset with sideways out cables and mount the lamp on the side without the cable.

rogerzilla · « **Reply #22 on:** 30 January, 2019, 02:18:54 pm »

My Moulton has white brake hoods, which catch stray light from a bar-mounted lamp at night. I quite like the effect.

Cudzoziemiec · « **Reply #23 on:** 30 January, 2019, 03:22:15 pm »

On some bikes with drop bars you get a brake-hood shadow thrown on nearby walls. I quite like that too, though it can be disconcerting when you first see it.

mrcharly-YHT · « **Reply #24 on:** 30 January, 2019, 04:01:49 pm »

Quote from: Brucey on 29 January, 2019, 11:43:48 pm

If you have a front rack, just attach a short length of 7/8" broom handle to it, (or a cork, or W.H.Y.) and mount the light on that.

cheers

That is probably a workable solution - some plastic pipe might work. bit of a pain reaching to adjust the lights though. I like to be able to switch them from low to high beam.