I have been a road cyclist for a long time and have used base layers only in colder weather. I always thought that base layers were meant to provide warmth when the weather is cooler. This past week I decided to wear a base layer that I originally purchased because I thought it would keep me warmer, but actually caused me to be quite cold. I didn't understand the difference between warm weather and cold weather gear. I wore this base layer with long sleeves on a very hot and humid day. And yes, it did seem to keep me cooler. This is causing me to reevaluate when I wear base layers. Do you all wear base layers whether it is cold or warm?

I split time between Florida and North Carolina. Riding in the heat and humidity in Florida, I find that a base layer for me just gets overwhelmed with sweat ands makes me less comfortable.

In NC riding in the mountains where it can be hot climbing and cold at altitude and descending, a good base layer that can wick moisture is and advantage.

So for me I use a base layer where the temperature and effort is going to vary with the altitude and terrain, and where the heat and humidity is not enough to just overwhelm the base layer’s moisture management capability.

I wear a wool Rapha one when I tour if temperature dictates. It can be in the highs 40s or low 50s when I hit the road but warm up relatively quickly. Remove it when no longer needed, Nicer than riding in a windbreaker or jacket.

I wear this throughout the summer, and cooler times. other variants. I like the compression aspect.

Bill, some additional background would be helpful. Do you live in a humid, dry, or in between environ in the summer? Do you typically sweat a little or a lot? Do you workout hard or are a more casual cyclist?

People are answering but that is from their specifics which may not apply to you.

I've got a string wife beater that purports to wick sweat away to keep me cool.
I purchased in a moment of weakness after a particularly miserable DNF on a 600k ride due to heat exhaustion.
I have no idea if it does what it says.
https://www.castelli-cycling.com/US/...028_001_58_L-X

have settled on the rapha merino wool base layers for the last decade +. have worn them to a low of 33 degrees and a high of 107 degrees.
both the short sleeve and long sleeve ones have lasted for the better part of two years when using 2x a week (gentle machine or hand wash-no dryer!!).
these days, i buy two at a time every other year to defray the wear and tear on any one particular garment.

ride mostly in southern california...beaches, foothills, deserts, mountains. obviously not the most humid area but the short sleeve ones work well
even in the triple digit heat range. yes, you're a little hotter but if you've got access to water besides what you're carrying on the bike, soaking it and then
putting it back on feels great. occasionally got a few sunburns through lightweight jerseys in the days before always wearing a base layer. haven't had a
sunburn through a lightweight/hot weather jersey since.

base layers are supposed to wick away sweat, thus in the winter it keeps you from pooling in sweat thus dropping your temp and in theory in hotter weather it help you from becoming swampy and soggy, granted it does nothing but restrict airflow, thus I doubt you were actually cooler just less sticky feeling. When it actually makes sense to cover IMO is when is insanely hot and bright out and covering your skin to prevent irritation and burns would occur

Always have a base layer on, hot or cold weather. More comfy as well with stopping any potential bibstrap rubbing. Summer sun, also adds a tiny bit of SPF protection when riding in summer-weight jerseys. Just ordered a 3-pack of gripgrab sleeveless -- looked like a decent value -- neither $50+ per unit, nor a typically itchy $10 offering. I also just use these for any indoor trainer riding, as they work well for keeping cool when your fan is running so they get used.

GripGrab ULTRALIGHT

I too wear baselayers all year here in Ohio, riding or not. My two favorites for summer are Defeet Un-D-Shurts and Under Armor Heatgear compression tops. I have all three styles of the Defeet, sleeveless, short sleeve and long sleeve. The UA Heatgear is long sleeve. I've been wanting to get the sleeveless version, but keep "forgetting". These work in the summer because as I sweat the fabric gets wet and the airflow of the ride creates a evaporative cooling. Air blowing through wet fabric against the skin = a nice chill. Even hot air. Take this morning for example, some low 70's degrees and humid, sunny, light wind. A Defeet sleeveless shirt under my tight fitting Sportful jersey and bibs. In the sun I'm hot and lightly sweaty. I descend into some heavily shaded ares near creeks where it's notably cooler, and the chilling effect is pronounced. I zip up my jersey all the way to stay warm. If you're not accustomed to wearing a baselayer shirt, especially a long sleeve one in hot and humid conditions, you will feel like you're almost overheating at first, until you start sweating and the fabric starts getting damp. Then you reach a perfect point of comfort. Also, if you stop for a minute while riding in the heat and if there's little wind, you'll also be quite hot until you start moving again. I've never felt even the long sleeves were too much while riding. Again, wet fabric with wind blowing over it = evaporative cooling effect. Long sleeves also keep the sun off your arms and they don't heat up like they do with short sleeves. When done with the ride your arms feel "normal" temperature. In all of this I'm referring to form fitting clothing, "second skin" like.

Duly noted, I'm a summer heat lover, I love summer, I love summer, repeat infinitum. I can even be sitting out in 90 degrees and humid and love it. Spray myself with a hose, of even warm water, add some good wind, and to me it's comfortably cooling. Needless to say, in the cooler season, controlling the wind flow from passing over sweat is a must for me, and there's a fine line between between "too much" airflow and "not enough".

I used to wear them in hot conditions just because I had cheaper bibs with straps that were uncomfortable and could rub. I stopped when I got better bibs, as I found a baselayer to be the exact wrong thing for my riding. I'm generating the most sweat and overheating when riding slower, i.e., uphill, and a layer soaking up warm sweat is the last thing I want between skin and jersey. Then once I'm descending and not generating heat anymore, the damp layer starts evaporating and overchilling me.

A good form-fitting jersey that is breathable and can both wick and allow sweat to evaporate quickly is far superior. My Rapha Pro Race Aero jersey surprised the heck out of my with how cold I felt on my first ride wearing it on a cool morning, and it isn't even a true lightweight or flyweight summer jersey.

I reserve my old "hot weather" baselayers for milder conditions (50-60F) or when I'm riding indoors sans jersey.

I use a baselayer in the warm months- usually a Craft Superlight.
It has a lot of stretch, doesn't gap in the neck or arms like some other brands/cuts, and feels good.

When it's 85 or hotter, I am drenched regardless of what I do or don't wear because all clothing is overwhelmed with sweat.
But 60-80 degrees?...yeah, the baselayer is nice to have and seems to pull sweat away. I definitely open my jersey more frequently with a baselayer because that creates a few minutes of cooling effect with the wind hitting the baselayer.
https://www.craftsports.us/products/...oaApVoEALw_wcB

Interesting studies presented on the effectiveness and non-effectiveness of summer base layers Base Layer tests. Maybe Larry was onto, or on, something.

TPC needs a proofreader. Do some of those studies precede the mesh style baselayers being prevalent, eg. these types


Big difference to the original base layers which were the heavy spandex, close weave, compression shirts

I live in the northern US. I need to wear cold weather gear more often than warm weather gear. The summer here can be hot and humid sometimes. I am not a heavy sweater. I have done triathlons and aquabike races for a long time. So I guess I am somewhat serious. I am intrigued by the short-sleeve base layers for the warm weather. The one I have is long sleeve, which just feels a bit counterintuitive for me.

^^^This. I honestly cannot tell whether any of the "technical fabric" garments I own -- whether they are base layers, top layers, mid layers, whatever... -- do what they purport to do. So I just wear the ones I find are comfortable.

In hot whether, that usually means no base layer at all.
On a day when the temps will start cool and get hot (or vice-versa) I'd rather have the base layer than not. Also because. all else being equal, a base layer prevents irritation from bib straps.

But I couldn't tell you whether my Merino wool base layers are any better at wicking moisture away from the skin than my polyester or polypropylene base layers. :shrugs:

I subscribe to the theory that base layers keep you warmer in the winter and cooler in the summer. So I wear a base layer 100% of the time.

I failed to see the logic in wearing more clothes to be cooler. But I also drink when I'm thirsty and eat when I'm hungry… so I'm kind of old-school.

Also might be worth noting that pros – the guys who have access to any equipment/clothing that provides an advantage – don't wear base layers when it's hot.

(Cue the internet search for that one pro who one time wore a base layer when it was over 70° - sun sleeves don't count. ;-)

What a pro rider or anyone else wears is their own business, "they" have no ifluence over my own, let alone anyone elses inherent thermostat.

As for photographic "evidence", it's the internet, it took me a minute to find this. I clearly recall seeing riders wearing baselayer shirts in the TDF at the time. This is 2006, stage six. Cycling is forever very trendy anyways, it's self-justifying. "Because I'm wearing it, that makes it right !". Ahahahahahahaha !!!!

You may be old school but that’s cool. I drink BEFORE I am thirsty and eat BEFORE I am hungry. From what I have read, is when you wait until either of those conditions occur, you are already in a hole and it’s harder to dig yourself out rather than fueling and hydrating preemptively. But whatever works for you.

Base layer year-round for me. In the summer I use sleeveless mesh ones. The open weave doesn't absorb moisture and keeps my sweaty jersey off my skin which feels cooler and more comfortable than having a saturated jersey stuck to me.

I have a few different short- and long-sleeve options for cooler/colder weather.

I always wear a base tee until the temps reach the 90s. For decades the mesh tank top style Performance ones. Now the grey Patagonia tee shirts. Still have the Performance ones and sometimes wear them in the very hot. I find jerseys last longer and stay nicer with those tees. I also get fewer surprises, like hitting the downhill after the climb I wasn't planning on. And after weather changes.

Speaking of weather changes - in an emergency and you need warmth - newspaper! A full sheet with the one long fold, pulled under your outermost jersey to your shoulders with a neat "v" ripped at the neck can be a rider saver, even a life saver. Pros have been doing this more than a century. It still works and they still do it. (Well not the well sponsored, highly public elite riders but the domestiques on the lesser teams who have been dropped, having done their work and need to descend and finish alone or in the grupetto, no team car around.) Look for quality newspaper. The good stuff doesn't shed ink. (In Portland, that is the NY Times. The Oregonian is just meh.)

I wear 2XU triathlon singlits year round. They offer additional support and breath well so I do not overheat and are form fitting with compression to prevent fatigue.

That's an idea.. let's all do selfies wearing just the base layer.

I have arm warmers for when I start cooler, but expect temps to rise past the upper 60s (sun), or mid 70s (cloudy). I don't know about my torso, but I definitely can't stand having arm warmers on when it gets warmer. That said, they're fantastic for when I start in SF and ride into Marin - it can be 60F in SF, 80F in Marin, and feel like 45F when crossing the Golden Gate.

As for a base layer, I've only stuck with one in cooler weather - though it's surprisingly comfortable to have a snug, long sleeve layer on when the temps are ping-ponging around 70F and you're cruising along at 30-35kph.