I am not acclimated to cold weather.

When I posted this question it had been cloudy and in the mid 50s for a few days. Sunshine does make a difference.

There’s a new fangled invention called a “rack”. It attaches to the back of the bike and provides a platform where you can put stuff.

https://cimg1.ibsrv.net/gimg/bikefor...df43240d6.jpeg

There’s a slightly newer fangled thing called a “bag” which mounts to the rack…rack had to come first…where you can put stuff you don’t want to carry around, like jackets and articles of clothing and lunch and keys and all kinds of other stuff.

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If it doesn't fit in a jersey pocket, it doesn't get worn.

My only piece of kit that won't fit into a jersey pocket is a thermal jacket with fleece lining. When I take that off, I roll it up from the collar down, then tie the arms around my waist. Rolling it up is important, so the bottom of the jacket doesn't get caught in the back wheel.

https://store.voler.com/products/101...41481024078014

I’ve always been of the “Dress for the Ride, not the Driveway” mindset. I know I’m going to be putting out a lot of heat after the first few miles, so I’d rather start out a little under-dressed than carry a bunch of extra clothes for 70-80% of the ride.

Also, I prefer a couple small pieces rather than a single over-garment. A vest (gillet) and arm warmers (or zip-off sleeves) also means you can adjust gradually rather than all-or-nothing.
Small pieces are easier to stash, too, rather than a full jacket.

That's probably because unlike you, we don't want our jacket sleeves have different lengths, have external cabling and don't want to look ghetto when riding when there are tons of neater solutions.

Firstly, as said just above, on a cool day you wan to be shivering standing at the ride start. Secondly, you don't need a heavy jacket. All you need is a wind jacket that will fit in the center pocket of your jersey. If it's cool, you should also have a wind vest either in that same pocket or a side jersey pocket. Your wind jacket should be no larger than a Naval orange when crumpled up. In the pouring rain, you stay warm in your wind jacket because you have adequate insulating clothes under it. Since you can't evaporate sweat to cool you when wearing a jacket, you use the slight amount of rain water that comes through the wind shell for that purpose. It's really quite simple, just takes a few realizations to adapt to the cycling mindset.

An alternative to a wind jacket or vest is one made with a more waterproof material. It packs down just as small, keeps most of the water out, and blocks the wind better.

I use a clear rain vest made from lightweight and stretchy "Crystal material", whether it's raining or just chilly. Perfect for long descents on cool days.

I use Voler's Wind Jacket. It has the perfect water permeability, lets just enough water through for cooling. My problem with waterproof is that it's also waterproof from the inside. "Breathable?" So far I haven't tried anything that was even close to being sufficiently breathable. We're water cooled when we exercise. Gotta get rid of the heat somehow. Suggestions? I saw that Gore had $400 jackets that claimed they could do that, but they only came in black and I don't see them anymore. They did look like they'd stuff small enough. My guess is that their new 3-layer stuff would be too bulky, but I haven't tried it.

The toughest weather I ever rode in was a 75 mile ride in a steady 36° downpour. We were so lucky that the temperature didn't drop. I have started rain rides and had to bail when it changed to heavy snow and I was scraping the ice off my glasses with my fingernails. Always that same jacket, worked fine.

Wow! Do they make those for any brand besides Cannondale?

I will look for a bag and foldable jacket.
I just needed an idea for when it’s cool when I start but then warms up. This morning it started around 52* and cloudy. Right not it’s much warmer- 65* and sunny.

Having done a fair amount of climbing on both bikes and skis, I can say that no garment ia breathable enough to evaporate the sweat when you're going uphill. Lots of strategically placed mesh and zippers are your best friends.

Gore has a "Shakedry" jacket that's very light and supposed to be very breathable. A buddy of mine has one and loves it. I think Gore has discontinued Shakedry, but the jackets still shows up on their website (black only):

RACE GORE-TEX SHAKEDRY™ JACKET MENS

52F is short sleeves and no glove weather.

What I'm saying. I climb fine in the rain in that Voler jacket. I change down to the vest or just take it off if it's not raining. One can take off the jacket and stuff it in a jersey pocket while riding or just stop for a moment. With any luck, all the riders in your group (if any) will decide to stop at the same time. My insulation layers are all synthetic, which don't hold water and dry quickly should it stop raining. I've tried wool and it sucked. I'm partial to Craft base layers, vests, and gloves. I haven't tried their jackets.

That Shakedry jacket is what I was referring to. If I were still mountaineering, I'd sure consider one.

Yeah, I used to use a similar wind jacket all the time. That got me into trouble on one ride, when I was climbing White Mountain.

The ride started out partly cloudy, with just a few sprinkles. It got progressively wetter and colder as I climbed. The last few miles were cold rain, wind, and lightning, and I was drenched and shivering while climbing as fast as I could, while worried that I was going to get hit by lightning.

I was much too cold to descend, but two guys in an SUV graciously drove me back down.

After that experience, I switched to carrying a more waterproof jacket. It definitely has kept me warmer on chilly descents.

https://cimg6.ibsrv.net/gimg/bikefor...f85388bc7b.jpg
Lick Observatory on showery day in March, Showers Pass Pro Tech jacket

Yes, that can happen. We have an event ride here which goes over a mountain pass. The event used to be scheduled for early June until one time it was sleeting on the whole west descent of 30 miles. Luckily there was an RV parked on the road side about 5 or so miles into the descent or simple survival would have been an issue. Everyone just crammed into the RV and waited for sags. A rando riding buddy knew he was going to run into that same situation on a brevet so he wore a rucksack crammed with warm clothing.

Does that Pro Tech fit in a jersey pocket?

Yes, it fits pretty well in a jersey pocket, as long nothing else is in the pocket.

After that jacket wore out, I bought a similar style from Pactimo. It's also waterproof (not the seams, though), but it packs down even smaller:

Pactimo Men's Ultra-Light Jacket

Yeah. I heard Gore is no longer making them because of environmental concerns I don’t know the details of.

I’m not, because it’s not, by far.

I use a light windbreaker that can squeeze into one of those small pouch type tool holders that fit in a water bottle cage.

Down to the low-40s, I will wear a base layer, jersey, arm warmers, and vest. The vest and arm warmers will come off progressively as the day warms up, and everything fits in a jersey pocket. On the rare occasion I wear a jacket instead of a vest, it’s lightweight and doesn’t take much more room in a jersey pocket than a vest.

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like many others - I would begin the ride with a lightweight shell that I could store in a jersey pocket

if it would not fit in the pocket I would not wear it

I had a lightweight Pearl Izumi shell - and also had a light weight paper-like (Tyvek ?) ‘Camel Joe’ gas station promo jacket (pictured above) … super lightweight and pack small

on some long rides with early morning start I would ditch (hide) the shell after an hour or two into the ride and then drive back later to retrieve the shell … one time thought someone took the jacket I hid when I forgot where I had stashed it

Yes, Pactimo's good stuff. My fave hot weather jersey is from them.

it’s the easiest and simplest for something that doesn’t fit in your pockets if you don’t have bags, don’t you do bike tours? You must know this to be true

I will look for a lightweight windbreaker.
I have been putting off buying a jersey until I lose more weight. I found one that I had stashed long ago. It’s long and has 3 open top pockets in back.

A couple of qualifiers there that are not included in your post. Take more time to compose. “A if X and Y.” instead of “A, period.”

That aside, I would stow it under my jersey first. Even securing it to a rack would be better (and easier). Lashing it to my frame would be a last resort, theoretically. In practice, I wouldn’t start out with a jacket that needed to be lashed to my frame because I would plan ahead and have an alternative.

For example. while riding back towards Montana from AB, I secured my bulky rain jacket to my rear rack, not my frame, because I needed to put it on for the descents and take it off for the climbs.


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