Pas Normal Studios Mechanism Deep Winter Long Bibs review: exceptionally warm tights in a race-fit style

The Pas Normal Studios Mechanism Deep Winter Tights are made from a three-layer fabric that features a Windtex Pro membrane. Internally, there’s brushed fleece with a grid structure to provide warmth against the skin. Externally the tights feature a DWR treatment, which in conjunction with the membrane aims to make these highly weatherproof. The internal fleece grid structure is designed to improve both insulation and breathability by enabling a level of internal airflow. Legs are ergonomically shaped to better fit around the knee with a slight articulation, while the front of the tights is raised to provide additional warmth around the trunk and stomach area. The straps are elastic and soft, with a mesh rear to aid breathability.

These tights, with their high front, interface perfectly with the PNS Mechanism Thermal Jacket that is cut with a short, race-fit front. PNS uses its own four-layer ultralight foam chamois, which is made from quick-drying materials and has an antimicrobial membrane to provide long-term comfort and reduced friction. This padding varies in density across the seating area to provide tailored support across sit bones and soft tissue. Size-wise the tights come in XXS to XXL, with five colours available. The recommended operating temperature is around 0˚C.

The ride

Using the PNS Mechanism Deep Winter Bib Tights, it is obvious straight away that they are designed for riding comfortably in the coldest conditions. In the range of testing temperatures I experienced, at no point did they feel cold, even in 0˚C early mornings. Indeed, at 10˚C my legs felt too warm. The internal fleece grid structure is nicely soft against the skin and does a great job of creating an insulating air barrier. The pairing of Windtex Pro material with DWR treatment makes these bibs nicely weatherproof. Water beads off the material with ease, even in heavier rain, while windchill is not a factor. The only issue is that the seams are not internally taped, and do allow some moisture in, making these seam lines a little colder when it’s wet.

The fit of these tights is interesting. Being part of the Mechanism line, race fit is the aim and the Deep Winter tights are a prime example of this. The bib straps are ever so slightly short on me when standing upright. However, when tucked down into a more aggressive position the pressure is relieved and the slightly longer rear panels of the tights make sense. The legs are also ergonomically shaped so that when pedalling there is limited bunching of fabric behind the knees. As with other PNS garments I’ve used, the fit does appear to cater for a shorter upper body, while being fine length-wise in the legs.

At the front of the tights, the fabric is cut high so as to provide more warmth around vital organs. This works brilliantly for cold weather but does make nature breaks very difficult. The straps are very comfortable, but with a white base layer worn underneath on the first two rides, there was some dye leakage.

The chamois pad is one of the stars of the show. PNS’s four-layer ultralight foam pad performs brilliantly at distributing pressure nicely across the seat area in both aggressive positions and relaxed ones. Over rougher road surfaces the vibration dampening was highly effective, so these are a pair of tights I can wear for very long rides over awful surfaces. I have another pair of PNS shorts with the same pad, and after about a year of use, I can confirm that the antimicrobial membrane appears to hold up well, resisting any long-term odour. My only issue with the pad is it needs to be in the right place to be comfortable. I found I had to pull the legs up quite a lot to get the pad sitting correctly without movement. This was because the legs were a bit tight but not constricting, and I have to concede that the material is not as supple as plain fleece-lined fabric with lesser weatherproofing.

Value and conclusion

PNS is a premium brand, which is reflected in the £280/$350 price. However, compared to the Rapha Pro Team II (£260/$335) and MAAP Team Evo (£245/$355) the Mechanism doesn't fare badly. The Castelli Espresso or Sportful Fiandre (£170/$189 and £150/$199 respectively) offer arguably better value but potentially less weatherproofing. There are also tights such as the Assos Mille GTO (£420/$570) which make the PNS look good value by comparison.

To conclude, the PNS Mechanism Deep Winter Tights offer a pair of bib tights that are exceptionally warm in colder weather, including sub-zero conditions. The weatherproofing is superb bar the seams letting in limited amounts of water, but even that does very little to detract from the warmth. For fast-paced long winter rides in even the coldest conditions, these tights are brilliant. While the price is premium, I do not judge it excessively high for what they offer.