Probably mid-40's, don't remember exactly. Pretty sure I also over-extended my knees by experimenting with saddle positions, but I still attribute at least 50% of my 3 months of knee pain to the cold. I was wearing tights, but they were thin running-style tights, not warm cycling-style ones.<br><br>
My new motto is - Ride in the cold, but save the hard bike workouts for the gym/trainer until the weather improves.
I for one can think of no situation where leg warmers might be appropriate ... I've lived through that hell already<br><br><img alt="" src="http://www.bernat.com/data/pattern/image/image_1594.jpg" style="border:0px solid;">
Probably depends how you ride. I hurt my knees by riding <i>hard</i> on a cold day with inadequate knee insulation. I'm talking multiple hill repeats at near-max effort. I've done lots and lots of rides at more "normal" effort levels without problems. On the other hand, maybe I was wearing better clothing...never really paid much attention until recently.
Maybe Jr will chime in when he makes the rounds... he is a huge proponent of keeping the knees covered at any temperature below 50-55F, and he has good reasons to back his advice. He's been riding since before the bicycle was invented, so he knows his stuff. I think I even saw him on the Tour once, but he is too humble to admit it.
I can only speak anecdotally. Last winter, I upped my mileage from 40 mpw to 50mpw as I trained for a Spring marathon. I ran in shorts down to 40 degrees and even the occasional 38 degree mornings. I battled soreness and tightness in my hamstrings for much of the training cycle. This winter, I've stuck to tights in all temperatures below 45 degrees. I even raced my HM in running pants since it was 32 degrees at the start. I have had 0 issues with my hamstrings this winter despite some 65 mile weeks. <knocks on wood>
I use both knee warmers and shorts with a "knicker" or built in knee warmer. When it's cold and rainy, I prefer to just use oil on my lower legs so the cuffs don't get all soaked and flappy, especially in a race. If it's really cold outside (i.e. low 20's) I'll use them under tights for an extra layer.<br><br>
I use arm and knee warmers nearly every month of the year around here, I love them, they are a tiny comfort when the weather is awful...<br><img alt="" src="http://i5.photobucket.com/albums/y173/jroden99/PA_water.jpg" style="border:0px solid;"><br><br><img alt="" src="http://i5.photobucket.com/albums/y173/jroden99/P4181607.jpg" style="border:0px solid;">
We go out dressed like the Stay Puft man this time of year, 3 jerseys, jacket, couple hats, mittens, shoe covers--takes longer getting dressed than actually riding. The good news is if you stack it you can slide a good long way before you get any road rash, the bad news is all those clothes cost a lot of money...
If it's dry, I'm outside. Bundled up but we get so few dry days in the winter that I need to take them while I can.<br><br>
I was so happy the weather was nice today. Got a good 30 mile ride in. Otherwise I'd be stuck riding by myself in my garage watching Harry Potter or dragging my trainer over to someone else's house for a 2-hr "we don't want to suffer alone" fest while I try not to hate him for talking me into it. <img alt="uhoh2.gif" src="http://files.kickrunners.com/smilies/uhoh2.gif">