Castelli NanoFlex leg warmers review

Ideal for use in changeable weather, Castelli NanoFlex leg warmers offer insulation and water resistance

Castelli NanoFlex leg warmers
Reasons to buy
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    Water repellant coating

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    Grippers work well

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    Attractive fit

Reasons to avoid
  • -

    Coating wears off

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    Fit not as ergonomic as other brands

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Castelli’s leg warmers utilise its water-resistant NanoFlex fabric, which is claimed to have the same breathability, stretch and warmth as the standard Thermoflex fabric. You may have seen Castelli NanoFlex leg warmers being used by the Cannondale-Garmin Pro team when the weather turns foul.

>>> Buyer's guide to arm warmers

The NanoFlex coating is hydrophobic, meaning it repels water. Castelli doesn’t claim the warmers are fully waterproof, but the fabric’s coating does a great job of repelling water, with impressive beading. The fabric dries fast once the rain relents too. Unfortunately the NanoFlex coating only appears to last a couple of washes, but it can be replenished using a product like NikWax or Muc-Off Fabric Protect. These warmers also feature a zip on the ankle for easy removal over cycling shoes.

>>> Better than a Castelli Gabba? Wet weather jackets put to the test.

These warmers are light and really comfortable. When on the bike, they don’t move anywhere, with the double-sided silicone grippers working well to also stop your shorts riding up. The fit is among the best I have tested with no loose material or bunching. They don’t feel restrictive around the knee either, with a good degree of stretch. However, other designs such the Assos S7 warmers offer a slightly more comfortable fit, owing to their ergonomic, multi-panel construction.

With a retail price of £50 they are not the cheapest, but the quality is good and I found they last a long time being heavily used before deteriorating. With regards to sizing, I am 6'1 and 69Kg with a size medium pair fitting perfectly.

For more information head over to Saddleback.

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