Castelli Sorpasso RoS Wind Bib Tights

Castelli's Sorpasso RoS Wind bib tights provide windproof protection for your working muscles, they're water repellent, and they come with an excellent seat pad. For keeping comfortable on cold and filthy winter rides, they're hard to beat.

One of the key factors of these tights is the Gore-Tex Infinium Windstopper X-Fast fabric which covers your quads, knees, and what Castelli euphemistically calls 'your most sensitive parts'.

> Find your nearest dealer here

Infinium Windstopper X-Fast lives up to its name by halting cold air in its tracks, which you'll particularly value when you hit a fast descent. It's a softshell fabric that's water resistant – highly water resistant, in my experience – with a deep fleece inner face, so you get plenty of insulation here.

The Infinium Windstopper X-Fast isn't as springy as a standard Roubaix fabric but you do still get lengthwise stretch, and Castelli has cleverly articulated the design around the knees, giving you enough freedom of movement to pedal comfortably.

I've used tights in the past with windproof panels that don't stretch much, so they either put pressure on your knees or, if they're cut looser to allow for this, the fabric ruck ups as you pedal. I wouldn't say the Infinium Windstopper X-Fast feels exactly like a non-windproof fabric, but it's about as close as I've ever experienced, and it's certainly not something I noticed when riding.

The non-windproof areas are made from Nano Flex 3G and Nano Flex Xtra Dry fabrics – Nano Flex being the name Castelli gives to its non-membrane polyester materials that feature a coating of tiny silicone filaments. These panels are warm and breathable, and the Nano Flex finish is water repellent, which is especially useful at the back where it stops any spray from your rear wheel soaking in. That back panel extends high enough to keep you well covered even if your jersey/jacket rides up a bit as you move.

Nano Flex, which has been around for many years now, won't entirely protect you from rain – Castelli doesn't claim that – but it does encourage light drizzle and road spray to roll off. Its effectiveness gradually diminishes over time, but you can give it a new breath of life by ironing the surface (yes, it really works).

You get YKK zips down at the ankles with pullers that lock into place. Do you need zips on anything you're not going to be taking off over your shoes mid-ride? I'm easy either way.

The panel that runs alongside the zip looks shiny black/grey in daylight but it's highly reflective to help you get noticed by other road users at night. Wearing overshoes on the outside of your tights will largely cover these panels, though, which is something you might want to consider if you're out in the dark.

Castelli specs its top-level Progetto X2 Air seat pad here. This provides variable thickness cushioning and includes gel-like padding in the perineum and ischial areas. Sitting next to your skin, you get a stretchy microfibre layer with a perforated foam backing. This seamless top layer isn't fused to the underlying cushioning – the two can move independently to avoid any irritation as you pedal.

There's a lot going on with this pad and it really works to provide superb comfort however long you're in the saddle. I can't praise it highly enough, and you don't need to worry about durability; I have plenty of these that have stood the test of time.

Up top you get seamless elastic bib straps with a rear mesh panel at the back to keep them in place, spread the load, and wick sweat away as you ride.

The straps are designed to lie flat. I must say that mine had taken on a furrowed appearance over the top of the shoulders after a few weeks. Eventually, I took an iron to them (the second time ironing cycling kit has been mentioned in one review; what's going on?) in order to get them sitting right again, and that worked fine. I found that straightening them out when they came out of the washing machine meant they dried flat.

Castelli says the Sorpasso RoS Wind bib tights are suitable for temperatures from -5°C to 8°C. It'll all depend on your own personal thermostat and how hard you're riding, of course, but I'd say that's about right.

> Buyer’s Guide: 24 of the best warm winter cycling tights

For me, I start to struggle without windproof panels on tights when the temperature drops below about 5°C, and all the fun has gone by about 2°C. With the Sorpasso RoS Wind bib tights, I carried on riding comfortably when the Beast of the East II hit the UK, the Infinium Windstopper X-Fast being the difference between enduring the conditions and actually enjoying myself. Plus, you need to keep those knees warm so that they'll look after you in old age. The coldest ride I went on this winter was -2°C, but it was considerably lower than that considering the wind chill, and my lower body felt fine.

Windproof panels always add to the price of bib tights, although the Craft Ideal Wind Bib Tights we reviewed recently were great value at £90. I reckon the fit of the Castelli tights is better, though, and so is the seat pad.

The Gore C3 Windstopper Bib Tights that featured on off.road.cc last year were £129.99 but reviewer Liam Mercer felt that the fit wasn't quite there. You have to pay £139.99 for the version with a seatpad.

Rapha's Men's Pro Team Winter Tights With Pad II use a windblocking, durable water repellent (DWR) fabric for the front panels, so they're a similar concept to the Castellis. These really impressed reviewer Ash, although they are more expensive at £210.

Summing up

The Sorpasso RoS Wind bib tights put in an exceptional performance. The Windstopper panels really work to keep you comfortable in cold conditions and don't inhibit movement, and the Nano Flex treatment helps keep you dry on wet roads. Add in an excellent seat pad and you have a remarkably good pair of winter tights.

Verdict

Warm bib tights with windproof panels for cold winter weather, and an exceptionally good seat pad