Doug64

I agree, especially on the hat and helmet cover. My head is as hairless as the proverbial pool ball, so I wear a hat on even moderately cool evenings. Base layers are a matter of personal preference, and how the rider handles various temperatures.

ecnewell 

Same here. During activity, a Merino baselayer and a softshell is comfortable for me down to about 40 degrees, lower if I'm really exerting myself. I'll add another insulating layer if necessary, but I only use an insulated jacket when it gets really cold or I'm not moving.

My go-to 3-season outer layer is the Outdoor Research Ferrosi Hoody. It's very breathable, waterproof enough for most light rain (I still pack a real rain shell), and blocks the wind quite well. I originally bought it for a four-day hike in Iceland, and it served me well.

But, OP asked for an insulated jacket, possibly for good reason. As others have said, I wouldn't bring down on this type of trip unless you're certain you can keep it dry. I am also partial to Outdoor Research because of their generous return policy: if you don't like the product, it doesn't fit, or it just wasn't what you expected, they will give you credit towards something else. That said, here's another suggestion: The OR Razoredge Hooded Insulated Jacket

tarwheel 

If you're looking for a lightweight insulated jacket for wearing OFF the bike, I highly recommend the Patagonia down sweaters, which are on sale right now at REI through May 29. It will pack down very small and is very light weight yet surprisingly warm.

Doug64

If you go to REI, check out the Patagonia Nano Puff Jacket while you are there. They are a great synthetic jacket with the newest generation of Primaloft insulation. We liked ours so well we gave them as presents to all our kids and to a couple grandkids. They are a little over your budget, but well worth it.

https://www.rei.com/product/102404/p...ff-jacket-mens

ecnewell 

Those are great! The nano-air is worth a look, too. My wife loves hers.

nun

I find the Marmot Driclime jackets to be amazingly versatile. It isn't exactly insulated, but it works great for 3 season touring and I'm comfortable down to freezing if I wear a couple of long sleeve polyester shirts underneath. My torso layers are.

Ground Effect Rock Lobster
https://www.groundeffect.co.nz/produ...nt=28749387267

EMS long sleeve Techwick
EMS Men's Techwick Midweight ZipBaselayer

Marmot Driclime Ether jacket
https://marmot.com/men-jackets-and-v...ket/52460.html

Marmot Mica rain jacket
https://marmot.com/men-jackets-and-v...ket/30900.html

JagR

Can't comments on all but the IMO the Marmot stuff does NOT breathe!

nun

Mica rain jacket is not very breathable, but the Driclime is great for mornings, wearing around town and riding in chilly weather. It has good pit ventilation and the fabric inside actually works and wicks moisture away.

Tourist in MSN

I always use a down vest. If it is too cold for that, I put a rain jacket over that (even if it is not raining) and a warm stocking cap. Packs down tiny and is easy to carry, very lightweight. There are several good down vests out there, I am not recommending any specific one.