zatopek

18 degrees Fahrenheit. Any colder and I am not riding.

Zaskar

Pre-Kickr/Zwift: 20 degrees
Post-Kickr/Zwift 40 degrees
Thanks technology!

canklecat

I've ridden down to 20F, but I wouldn't call it training, unless casual rides count as zone 2 base rides. Hardest part is keeping the toes and fingers warm.

But this winter I've battled constant sinus inflammation and painful congestion, so I'm avoiding rides below 50F, especially in dry weather. I've enjoyed riding a few times in chilly damp weather or even light rain -- feels good to the sinuses. I can dress for wet weather, but can't wear a mask without feeling like I'm gasping for breath, which limits me to very easy effort rides.

Ghazmh

I don’t have a limit

I.B.Roots

I'm at 30F..anything lower doesn't interest me regardless of how many layers I wear.

Voodoo76

Less than 50F I'm inside. Greater than 100F I'm inside if the plan is interval work, no issues doing endurance pace in the heat. I trained and raced in early season cold weather (MI) for many years and know how to deal with it, just don't care to any more.

Lrdchaos

Roughly 40 If it’s sunny, or 45 if it’s cloudy/windy. I don’t race so it’s all about enjoying the ride...and I don’t like the cold.

kraftwerk 

Anything above freezing is lovely, below that, I don't have enough body fat or technical gear to sustain a real workout.... an errand maybe?

tomato coupe

Zero K

MinnMan

I'm not sure what you mean by "training" per se. Winter outdoor riding is about base miles as far as I'm concerned*. And pleasure. Winter riding is fun if you have the right gear. If I do anything like disciplined training in the winter e.g., intervals, it would be on the trainer.

(*Also, the snow and ice are really good for improving bike handling skillz!)

The coldest ride I can recall was last winter during the polar vortex, -13 °F. The coldest so far this year has been around -6°F. I regularly ride in the single digits.

This is from two days ago (Sunday). Obviously, the high temperature spike was stopping at the coffee shop to meet friends. The low temperature through most of the ride was +1°F. It was a very pleasant morning ride.

Seattle Forrest

I've been out in -10F. Night skiing. With the right layers it's not an issue.

jpescatore

My normal answer is if it is sunny, 35 degrees. Cloudy, 40 degrees - below that and Zwift on my trainer in the basement is more fun.

But:
I just finished a ride across Florida with temps in the 80s, got on Amtrak in Jacksonsville to Washington DC where 14 hours later at 0630 it was 23 degrees. Put on my cold weather gear, two layers worth, put bike on Metro train which got me to within 10 miles of my house - at the Glenmont station it was 17 degrees! But brilliant sunshine - well as brilliant as the sun is at 8am...

Heading towards my house, the first stretch is downhill where I hit 20 mph - and I thought my face would fall off. I don't even own, so wasn't wearing, one of those bank robber face mask deals. The climb back up defrosted my face, and at 12-15 mph it wasn't too bad in the sun.

But, if by training you mean biking fast - I now know that 17 degrees is too cold for me for that, unless I get one of those bank robber masks, which I don't.

There were a few puddle areas that were iced up, none on the riding surface but that is one reason I avoid riding under 32.

travelerman

40 degrees F... if it's sunny and not too windy. I prefer 85.

FlashBazbo

Back when I raced Dirty Kanza, I trained outdoors throughout the winter -- with weekday rides in the dark. And because I felt the need to "toughen up" for whatever weather the DK200 might throw at me, I didn't place a limit on temperature. But when temps got below 20*F, I had to cut some rides short. At those temperatures, sports drink turns to slush (and won't pour through a water bottle nozzle) in about 30 minutes. That generally meant I didn't ride more than 90 minutes when the temps were below 20F.

TheDudeIsHere

Coldest I ever trained is 45 degrees on rides up local mountain roads. It's SoCal so it doesn't get too cold here. On a night ride, fun ride, no training, it was 39 degrees, no problems with proper duds.

But I did have a good laugh at a rider after the training ride through the mountains. I was wearing shorts, under layer, and a jersey that day, 45 degrees at elevation. The next day I went down to the trail to do an easy spin on some flat terrain. I stopped at a park, some dude rolled up and said that I must be freezing. I was in the same set up but I was not cold.

He was wearing full finger gloves, face cover, shoe covers, jacket, and tights. Pretty funny that he thought I must have been freezing in the killer cold weather of 65 degrees. Ha ha ha, us silly SoCal people!

Froomewannabe

i would say use your gym money and buy a smart trainer. Last year rode down to 32F. Told my wife not to ever let me go below 32. I bought a smart trainer this summer. I haven't been out below 50 this winter. I like being able to ride when I want, ie I don't have to wait for it to warm up outside and just go get on my trainer.

Greatestalltime

I find if I can take the teens I can take single digits. It’s all cold. I have only missed one day the last three years and that’s because my wife said the snow hadn’t been cleared at all.

I don’t like it, but I hate the trainer.

Hmmm

30F and my glasses hurt where they touch my face for the first 10 minutes. If I stick to hill repeats its not bad. The warmth of Uniqlo heat teach base layers is very real.

waters60

Weekdays for Sufferfest and running. Weekends for long easier rides down to 18 deg and longer runs. I greatly enjoy the fresh air and a break from the basement. The biggest problem is my blood red eyes. Even wearing glasses the cold air wreaks havoc on my eyes. Painful, but worth it!

wipekitty

My training (that is, putting in a good effort, getting the heart rate up, hill reps and such) is really limited by snow and ice rather than temperature. In the cold places I've lived, snow and ice usually tend to turn up around 20F.

I'll ride at temperatures below that, but it tends to be slow and technical. I'll do hills on studded tires, but the game is as much about keeping traction as it is getting up the hill. As a result, rides tend to be much slower and easier (from a fitness point of view) and more about getting out and enjoying the sunshine than keeping up with a summertime level of fitness.

Sadly, the trainer is the only way I've found to keep fit when all the roads are covered in ice and snow. Running or cross-country skiing would probably be good options, but I don't do that.

TricycleTom

Riding for fitness, I move indoors before things freeze up, but I'll go for a sunny ride pretty close to that cutoff. As a young commuter, I'd just ride faster to stay warm as the temperature went down, but at -35C (`-30F) my lungs would start to freeze so I'd have to back off and get a chill. With a full-face helmet and a breathing tube to conserve heat and moisture, there would be no real comfort limits, but big boots and pedals need custom fitting, and heated gloves would be nice.
I used to commute in Toronto, and pull up at stop lights with a line of bus passengers shivering in their Dallas fashions. Occasionally, one would be so astonished that they would break the Code of Silence to exclaim "Aren't you cold?"
I'd grin, unzip my jacket, and flap it a bit. "Heck no! I've got central heating!"

sauerwald

I used to have a 14mile commute in Maine, and bottles would freeze in the winter. Put them in the cage upside down, and you can still drink since ice forms on top first.

My low temp was 0F, but that was commuting, not training.

wojowojo16

this morning was 32 and dark - did 20 miles

adamrice 

If it's dry and not too windy, I can get comfortable at temperatures down to the upper 20s. It's the cold/windy/rainy combo platter that makes riding miserable for me.

Chubby715

I live in the Northeast, (Fairfield CT) so 30F seems to be my cutoff temp. I also don't bother if the winds are over 20 mph or the roads are wet. My biggest pet peeve is keeping my head warm.