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Castelli Nano Flex+ armwarmers review

4 May 2018

Besides an uncomfortable silicon gripper, these are as comfortable as it gets

Cyclist Rating: 
Warm and great for changeable conditions, good length
Tight gripper at the top of the arm

This week's weather is testament to why dressing right for cycling in Spring is so important. In one ride you can be greeted with blazing sunshine, sideways rain and howling wind. You need clothing that can tackle any weather conditions.

Among the most important items of clothing in this period are armwarmers. A good pair of armwarmers keep you warm, as the name suggests, help keep you dry, are comfortable and can be easily stored in a back pocket if the sun decides to make an appearance. 

The Castelli Nano Flex+ should be in that bracket of 'good'. It's been seven years since they first launched and they had remained largely unchanged until this season. For an item to go unchanged for that long suggests its pretty close to perfect. 

After having used the Nano Flex+ armwarmers this Spring, I can now see why very little has gone under change.

Buy the Castelli Nano Flex+ armwarmers from Wiggle here

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Despite Castelli only rating these as three out of five on its website for insulation, I found them to be very impressive when it came to keeping me warm. 

I tend to ride after work in Spring. A quick 90 minute spin once I get home sees me scuttle around the Kent lanes as the sun begins to set. When that sun sets, the temperature drops significantly, from double digits to single very quickly.

On every occasion this happened, the Castelli Nano Flex+ armwarmers kept my arms just as warm as a good windproof jacket or long sleeve jersey could.

They were even better in the rain with the Nano Flex fabric keeping my arms bone dry no matter how hard the rain fell. 

With how good the armwarmers are at keeping out the elements it could suggest that they are not very breathable and can see your arms boil in the bag once the sun comes out.

Thankfully, the Nano Flex technology is also pretty breathable, dispersing heat from your arms evenly and efficiently.

Occasionally my arms did begin to raise to an uncomfortable temperature but this was only after big climbing efforts which is to be expected. 

Even if the warmers were too warm it's not much of an issue. Slide them off and neatly fold them three times and they comfortably fit in the rear of any jersey. 

The change that Castelli has alluded to after seven years is the addition of a lighter fabric on the elbow section which has been introduced to give more flexibility and bend around the joints. The same has been done for the matching kneewarmers. 

Lack of flex was never really and issue and I found stretching my arms in and out comfortable at all times with no real feeling of restriction. 

The only complaint I would make would be the ratio of fit from the wrist gripper to that of the upper arm. I tested a size large which were a perfect fit in all compartments baring that of my upper arm.

I found it slightly tight and uncomfortable at points despite the wrist, forearm and elbow fitting perfectly. I wouldn't say I have particularly large arms so it seems as if the sizing could be adjusted on the bigger sizes.

Only a minor point but nevertheless an issue.

It was slightly jarring that this was the case considering that the armwarmers were of really good length. I have extra long arms that are not too dissimilar to that of an ape when I let them dangle down towards my knees.

Yet thankfully, the Castelli Nano Flex+ armwarmers reached suitably underneath my jersey sleeve and reached my wrist.

Realistically, these Castelli Nano Flex+ armwarmers are good enough to see me through all occasions and it will take something very special to replace them as my go-to warmer, which is enough of a testament to their quality.

Buy the Castelli Nanoflex Nano Flex+ armwarmers from Wiggle here


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