If the energy from the sun soaking into your jersey is making more heat than you are at around 20% metabolic efficiency, it's either extremely hot where you are, or you're not doing much in the way of power production. If a jersey is constructed well enough to release body heat and wick sweat, you will never notice the heat from the sun, because there's more heat going out than there is coming in.

I ride in +90º for about 5 months of the year, and some days everything I'm wearing is black. My shoes are black, both of my helmets are black, all my socks and bibs are black. The only thing I have in an array of colors are jerseys-- and the lightweight, "summer" jerseys are lighter because of their construction, not their color. The lime green, the royal blue, the black, the orange-- I would never be able to determine the color of the jersey by the heat. Two of my favorite jerseys are black, and if the non-science by the "black is hotter!" crowd was in any way correct, I could wear it in the winter and stay warm. But that's not how it works.

A hot jersey will be hot regardless of the color. And vice versa.

that's true, I have never noticed a difference. I have a black long sleeve and a black short sleeve jersey. I think it would be really hard to notice the effect, it's not like you would have a way to compare easily by switching.

"sweat more you'll like it" is not a theory i buy into

I saw a skinny guy all in black collapse on a climb during a long event ride I was on. He was even wearing long sleeves. Before he dropped, he was riding sitting up, with his arms held out to catch the tiny breeze. Good bike handler. It was about 104° according to my Garmin. I was in yellow with white sunsleeves and not having any trouble other than it was hard work climbing 7% on our tandem with 100 miles already in our legs. The aid car was busy that day.

Article about visibility on the bicycle ... what works, and what, apparently doesn't work as well ...

https://roadbikerider.com/riding-ski...ist-visibility

"White" or "black" only tells you how much of the visible spectrum will be reflected or absorbed. Less than half the heat from absorbed sunshine is in the form of visible light. The majority is infrared (IR) and a small fraction is UV.

A fabric that appears black but absorbs little IR may well be soaking up less energy than something that looks white but absorbs all IR. Google for "coldblack" fabrics about products that are based on this concept.

If you google the subject you may also come across mentions of a study on black clothes wore by Bedouin tribesmen in the Negev desert that showed little difference between how hot you feel in black or white clothes. One caveat with this is that Bedouin clothes are worn rather loose-fitting, allowing convection to carry away heat between the fabric and the wearer's body. Cyclewear on the other hand is usually quite tight-fitting. So this study may not translate very well into the cycling world.

Coldblack - maybe. I haven't worn it, but I have ridden with cyclists who peeled their coldblack sunsleeves off while I was comfortable in my white ones. One would have to put a coldblack on one arm and a white one on the other and see what happened. Which of course ignores the visibility issue but then the black clothing advocates do that anyway.

the winner of today's TdF stage was wearing mostly black head to toe, I am not a world class athlete so I'll just stick with life experience... apologies for taking up forum space with a non issue

Like a few others here, I have black jersey's, white, blue, green, etc. I don't notice any different on back to back days of similar temp and humidity between a light colored one and a dark colored ones made of the same materials. I do note the differences in the Jersey materials tho. I have some light colored jersey's that are hot...and I have some that keep me much cooler (same with dark colored ones). That's my experience.

No arguments on the visibility factor. That's a given.

Totally agree, but I live in Australia and *always* wear some kind of bright colour or flouro vest. I also run lights during the daytime when riding on anything other than slow urban roads (and mostly then as well). As a car driver, I regularly observe groups of cyclists and have no doubt that those wearing bright / flouro colours and/or flashing lights are significantly (sometimes dramatically so) more visible than riders with normal or dull coloured clothing.

I have no doubt that it could be a life and death difference in many cases. I may look like a dork, but I do everything I can to be seen by drivers.

Interesting about the visibility of yellow vs orange. I can see that this could happen in some places, but I can't think of many places in temperate climates with greenery where yellow would not be visible. It's all about standing out from the surroundings - a sort of anti-camouflage!

So does europa.


(and Rowan and me)

you were lucky you didn't notice that material is basically see-through. I wonder if they get sunburn under it

That was around Gosford and we were working in the bush alongside the roads. I've noticed similar since and had it reported since, but I think the move to fluoro colours probably makes the point moot.

That world class athlete was told what to wear by the sponsors, just like he was told what bike to ride (unless they're doing the old change the stickers trick). At least we have a bit of choice.

Wasn't a non-issue. We often ask questions that turn out to be so, but equally, we often ask questions that had answers we didn't expect... and most of us are learning from questions we're glad someone else was silly enough to ask

There was considerable discussion at national committee level on the conspicuity of the new Audax Australia kit. The person driving the design project works also for Orica (yep, same one as TdF team), and consulted with the OH&S boffins there.

It seems that conspicuity is very much background dependent. For example, someone riding with a yellow jersey on roads among fields of in-bloom canola will all but disappear. Try Australian wattle flower for a similar trick. Orange does seem to be a colour that would have trouble blending with anything found on a worksite or along a roadway.

Bright, fluoro colours certainly are effective. Probably the least effective, in my experience, and if I recall from research a long time ago in the auto sector, blues and reds rate among the most difficult.

The issue of conspicuity is one that has been discussed here before. One of the most significant issues that exists, however, is that a cyclist can wear black, blue, orange or any other colour/combinations, but if they are hunched over the handlebars, so the biggest areas (front and back) are hidden from view front and rear, then conspicuity doesn't matter that much.

Next time you are out ona night ride with someone ahead wearing reflective apparel, note how much of its isn't seen, unless there is generous band across the butt area.

As to heat -- I've worn black jerseys from time to time in moderately warm weather. I've not really noticed any difference in heat transfer to my body. The breeze created by riding, and my sweat help moderate that.

I also am someone who wears long sleeves in hot weather to held reduce sunburn on the arms. This is the same at work (in cherry orchards). I have found Coolmax to be pretty good at helping to make me heat tolerable in warm to hot weather.

Off topic but related, more and more I am seeing other bikers using lights both front and rear during daytime while riding.

For years I have used a flashing red taillight in daytime when bike touring or when road riding in overcast conditions. Sometimes two taillights.

But in the past few years I am frequently using a headlamp too. This is coupled with the purchase of dynohubs, if I was still using battery powered headlamps I doubt that I would be running lights up front. But with a dynohub, since I can't even feel the extra drag and with LED lights that don't burn out, there is no reason not to leave them turned on unless I am charging something with a USB charger.