Matt, my current bike, which will very likely see me out, is not yellow (my first choice) because:
1. I'm getting on a bit for bright pastels. I drove bright sunflower yellow Porsche into my 30s, so I gave up that wonderful primary colour most reluctantly.
2. There was a waiting list for a yellow bike. There always is. It is a law of nature.
3. My particular bike, in whatever colour, is an historical artefact, in that it is a modernisation of a famous design first built in 1936. Coachlining was available only on certain colours by a chappie, then 89, who worked on the line when the bike was first built in 1936. Coachlining was not available on yellow...
4. At the time I was feeling nostalgic for a British Racing Green with gold coach lines Bentley sports car I built on a Mk VI chassis and had been foolish enough to sell to a silver-tongue American with a bottomless bank account. I was even considering going to the considerable expenditure of money and time to build another one.
5. A BRG frame in the right size was the demo bike for the coach lining. I could have it immediately, if I ordered it fitted out with approved parts in stock or immediately available.
6. Also, for taking the green "used" one, rather than lengthen an embarrassingly long waiting list for a yellow one, I was offered a €1300 and something discount (about two thousand dollars in Dan's money), and favourable shipping terms (which are worth hundreds more when you live four countries and a couple of sea passages away).
7. I've been very happy with the dignified green and gold bike. But I won't pretend that every time I see a sunflower yellow bike I don't wonder if I should order up a yellow frame...
8. It may interest Dan that BRG (actually a colour that translates from the German as "non-RAL forest green" -- BRG is whatever the designer says on the day it is, see COLOUR FOR PROFESSIONAL COMMUNICATORS in the series Graphic Design in the Computer Age
http://coolmainpress.com/andrejuteGDitCA.html ) photographs black, as for instance in the Rivendell joke bottom right of the 2nd page of
http://coolmainpress.com/AndreJute'sUtopiaKranich.pdf 9. My bike colour was therefore chosen for a concatenation of eminently rational reasons. None of them would have mattered if a yellow one were available. However, it would, for me in my circumstances, have been the wrong colour, far too aggressive and obtrusive. By luck I got exactly the right colour.
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I had yellow Ortieb panniers, now sold on for reasons nothing to do with the colour (I live in a low-crime environment) but with their usability on a utility rather than a touring bike; they're not intended to be opened every few minutes. They certainly added security for bike and rider at junctions. I replaced them with more convenient open-top Basil pannier baskets, of which i keep only one on the bike in normal use. My feeling is that highly coloured panniers would also attract the eye of everyone else, including light-fingered types. Someone in another thread recently made the point that black Ortliebs anyway have huge reflectors on all sides, and that may well be the operative consideration. I operate a BUMM IQ Fly front and Linetec rear lamp whenever the bike moves, including as daylight running lamps, and consider that sufficient visibility. I do however have a broken reflective Sam Brown belt strapped around the bottom of the pannier basket to hold it more securely to the offside chainstay and that definitely adds visibility from as much as a quarter mile out. I also have spoke reflectors front and rear, and of course my Big Apples have huge reflective circles on their sides.
Frankly, while I certainly consider a yellow motorcar a warning and a safety measure, the tubes on a bike don't have enough substance unless they are painted in reflective paint, so I don't think the colour makes you safer, especially from the front or the back. Only a few days ago a sunflower yellow motor cycle passed me. From the back all I could see was black fittings and a red light. Next I came up on a German tourer, female, on a custom pink bike, and from the back there was nothing of the pink visible, nor from the front.
If you want to make your bike glow in the dark, mix 2% black into primary yellow, and respray. It doesn't have to be a perfect job because the reflectiveness hides all kinds of poor preparation.
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I can't tell you what to choose. I'll just say that anyone who says he doesn't lust after a yellow bike -- is definitely a bad liar!
Andre Jute