Castelli Alpha RoS Jersey Review
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The Castelli Alpha RoS Jersey First Impressions
Right off the bat, the term “Jersey” in this case can be a bit confusing. It is sort of a jersey/jacket combo with a liner on the front and what seems like more of a slightly insulated jacket or wind breaker. The all-in-one cycling layer, I suppose.
The RoS has the qualities of a lightweight Jacket that is great for shoulder season riding. Cooler mornings that give way to warmer temperatures as the sun rises will be a perfect application. That said, here in our mild Front Range Colorado Climate, the winter day rides reach 50’s and 60’s with sun. Up until now, I’ve really enjoyed donning this on some 30 to 50 mile rides. And of course, there’s that “Rain” element that features in the title. We haven’t had much, so I’ll await patiently to be caught in a nice downpour.
Fit of the Castelli Alpha RoS Jersey
If you are familiar with Castelli, you know that their cycling apparel is constructed of high quality materials. The fit is what you’d think a professional cyclist would be outfitted in. It has a snug or very race-like fit depending on your body physique and level of fitness. If you haven’t had the pleasure of wearing Castelli gear, do take careful note of sizing. Sizing charts are readily available on their website and I’ve provided a version below. Please note, you will more than likely have to size up one full size.
The chart will help you dial in your exact size, so you don’t have to do a return/exchange. My go-to size for most tops and bottoms is a Medium, but I went with a size Large on the Castelli Alpha RoS Jersey. And even with that, she still fit on the smaller side. No room for error, so check HERE.
Testing the Castelli Alpha RoS Jersey
I must have wanted to forget that the S in RoS means “Shine”. To excited to take my new test gear for a cruise that I willed the “S” to be snow. I put my kit on, and went out in low 20 degree temps. Clear roads, but snow on the ground with big blue sky fooled me into thinking that it would be fine. It was not! It really didn’t matter too much as I only had a short commute. From now, above freezing temperatures are probably as low as I’ll go.
I always like seeing what the cold and hot temperature limits could be for my gear. I received this Jersey in February, but with amazing Colorado weather this winter, it has allowed me to get out to enjoy the 50-60 degree days.
My weather index on the warm side for the Castelli Alpha ROS Jersey is about 50 degrees especially with some sun out. Unzipping the outer layer will help get good airflow going, but if you know it’s going to be warmer, I’d plan accordingly. The built-in base layer with the ProSecco Strada liner on the front has its own zipper. It almost acts like your climate control options in your car. Turn up the AC by unzipping the outer jersey to allow for cooling and airflow throughout the body’s core.
I am excited to test out the Castelli Alpha RoS Thermal Jersey this summer while playing in the mountains and going over some high altitude passes. Weather can be finicky up there, so having a piece of gear like this will definitely help fight anything mother nature throws my way.
The technical specifications and their impact on my rides
- Windstopper 150 front and sleeves. A key component of this Jersey, and has been a real bonus as I’ve encountered some fierce winds with fronts moving in.
- Nano Flex Xtra Dry back. I’m still waiting for some more inclement weather to test the water protection features, so I’ll report back on that. The insulation feature on the backside is good. It keeps the warmth in, and does allow some heat to escape. I have noticed when the effort steps up that not all of the perspiration disappears. Maybe a future generations could figure out a way to include another mesh jersey portion or vents for additional breathing.
- ProSecco Strada inner liner with 2nd front zip. A very unique feature that allows for use in many conditions which makes this the shining star of the Castelli Alpha RoS Jersey. The variable uses are what helps make this a truly unique piece of apparel in my cycling apparel.
- Waterproof YKK Vision Zipper. YKK is an industry leader. Hence, no surprise that this is featured on the Castelli Alpha RoS Jersey. The inner zipper is a smaller version, so take an extra moment to handle that one with care.
- Articulated Collar. It’s slightly insulated which provides warmth and comfort when there’s chill in the air.
- Front Zippered Pocket. I am going to assume they mean SIDE Zippered Pocket! I am not a fan of front pockets in jerseys and this one does not have any, which is good. There is however, a small side pocket. It is very indiscreet, but I absolutely love it. It is small, but just big enough for my wallet. I used to put my I.D., credit card, emergency contact information, and a $20 bill in a plastic sleeve. This would then go in one of my back pockets. I don’t have to do that now, and worry if it has fallen out if I’ve gone for a nutrition bar or something.
- 3 rear pockets with reflective laser-cut drain holes. The pockets are nice and deep allowing for plenty of storage of food, phone, and equipment. There is a slight stretch which prevents anything from working its way out and keeps larger clothing articles in position. The drain holes will come in nicely if I am ever caught in a downpour. The phone will have to find a better spot in that case.
- Raw edge waist. Super excited about this feature. It really does move with me as I am riding or when I’m off the bike. There’s no excess flapping or riding up.
- Advanced Patterning. This makes for a visually attractive piece of riding gear, but really does make for a close-to-body fit. Even though I am not the fastest in the bunch, this at least makes me feel a little bit more aerodynamic and sleek.
Below are Castelli’s ratings. You will notice up on the top, I have given these features my own rating. Not too many variations, and this will ultimately come down to each individuals perception of how these elements work for them. This could change several times during one single ride, depending on the conditions and effort level of course. It’s a great guideline to get you started, but you are more than welcome to upgrade or downgrade these features as you see fit.
Sizing is very important in that it is usually on the smaller or snugger side, and feels and looks more like a racing style. That doesn’t mean you have to be some super elite racer, as Castelli’s gear is top-notch, lasts, and protects you from the elements. Just keep it in mind, that’s all. The versatility in the Castelli Alpha RoS Jersey comes from the ability to tackle a good range of temperatures as well as wind and rain. The water protecting Nano Flex Xtra Dry front and back help repel any moisture if you get hit with an unsuspecting storm. I am definitely a fan of this piece of cycling apparel. It will set you back a fair amount, but having the right gear pays for itself over time.
It comes in three different colors: Light black/black, a ceramic blue/black, and an anthracite black/black. The last one is the one I tested, and I really like the orange highlights on the shoulders. For more information and purchase please check it out on www.jensonusa.com or www.amazon.com/castelli.