Sidi Algor winter shoe review: warmth and grip even when the trails demand a little walking

Whilst overshoes and normal summer cycling shoes work OK for many people when road riding through the winter, this is a less suitable combination when it comes to off-road riding on a gravel bike in cold weather. The problem is that the worse the weather, the less rideable trails might be so there may well be sections of walking. Pushing your bike along a rough, muddy or snowy track is a surefire way to trash your overshoes.

All of which is a long-winded way of saying that winter boots are much better than overshoes on a gravel bike.

Sidi has a large selection of road and off-road cold-weather footwear, and the Algor sits towards the less expensive end of the range. This part of their offering is a bit confusing though; there is the Nubes Road shoe, the identical-apart-from-the-sole Nubes MTB shoe and the Algor MTB which also looks exactly the same as the Nubes MTB but has some Primaloft insulation in it. The Nubes MTB and Algor are svelte enough to make ideal winter gravel boots as well as mountain bike shoes and benefit from Sidi’s move to their new Millennium last which moves their sizing more in line with other brands.

I had the Algor and the Nubes MTB to test, and were it not for the word ‘Primaloft’ on the side of the Algor, I would not be able to tell them apart. For an extra £30, I don’t know why you wouldn’t choose the theoretically warmer Algor though. For this review, everything I write applies equally to both shoes unless specified.

Both the Algor and the Nubes MTB (and the Nubes Road) are only available in black and in sizes 40-48. The size 44s weighed in at 1,008g.

Construction

As you’d imagine, Sidi’s off-road shoe has a chunky, grippy outsole. It’s a simple design with three large lugs at the back, raised grips around the 2-bolt cleat area and two triangular lugs at the front. These are made from a harder material than the rest of the sole as they are in a high-wear area, but there are also two holes behind them to add spikes or studs if you are struggling for grip in mud. These are not included with the shoes though.

Sidi rates the Nylon/carbon sole as 5 on their stiffness index, which is at the softer end of the scale - I only managed to illicit a tiny amount of flex by hand though, so they certainly aren’t slipper-soft. Getting cleat alignment right should be made a bit simpler by the multiple markings on the sole.

The upper consists of a low, internal shoe wrapped with a burly, waterproof TPU fabric, joined together at the junction with the sole unit. This shell is closed using a waterproof zip up the front whilst the inner shoe has a Quicklace Closure; basically a thin lace with a cord lock. The top of the ankle has a short Velcro tab and there are two tabs to help put the boot on and take it off. A small patch of reflective material on the front and a reflective Sidi logo are nods to nighttime visibility.

As mentioned, the Algor also has a thin layer of Primaloft synthetic insulation in the shoe which is missing in the Nubes MTB and Road versions. The insole is maybe a little thicker than the norm for warmth, but nothing too noteworthy.

The ride

The long zip and low shoe make the Algor easy to put on, and the new sizing seemed spot on - my usual size 44 fitted me as I’d expect. They still aren’t the widest shoes though, and there are no wide-fit versions available so the Hobbit-footed may need to look elsewhere.

A period of snow and sustained cold gave the perfect opportunity to test the Algor on rides where the temperature was still down at -5° mid-afternoon and conditions dictated periods of walking through the snow. Four hours later, my feet were still warm and dry, which is very impressive, so although a product's warmth is pretty subjective, the Algor’s get a big tick in the ‘warm feet’ box from me.

Less impressive though was the heel fit. I do have narrow heels, but given the slimness of the shoe as a whole, I can’t imagine many wide-heeled riders fitting the boot anyway. The main issue is that the lacing system stops very short, probably at least one hole less than you’d expect. Coupled with this, the zip merely closes the outer cover rather than taking in any slack and the Velcro tab does little more than enclose the zip. All of this resulted in a less secure heel than is optimal.

Clearly, these aren’t shoes that you are likely to be winding up for a sprint finish in, but equally, it is quite probable that you will end up walking a little in them and this puts a lot of pressure on heel security. Don’t get me wrong, it wasn’t a huge issue and didn’t cause me any problems, but it was something I was aware of to the detriment of the feel of the shoe.

My second criticism is related to the first - the fit around the ankle wasn’t great on my skinny ankles, with no way of cinching the top of the shoe in. This wasn’t a problem in terms of fit, but did leave a bit of a gap at the front of my ankle which was perfect for catching mud and snow flicked up from the front wheel. Maybe I just I need to work on getting fatter ankles!

I am also a bit dubious about the use of a zip on an off-road shoe, particularly one that is located right in the spray zone of the front wheel. It is a quality YKK waterproof zip, so should be up to the job, but filth-encrusted zips tend to cause problems in the long run - for the record the Algor zips have worked fine for me so far though. On the subject of zips, I wasn’t too keen on the relatively small plastic pull tabs either. Doing up a sturdy waterproof zip requires a bit more effort than normal (particularly if dirty) and I wouldn’t fancy trying to grip the tabs with cold, wet fingers. I think I’d add a small loop of cord for this eventuality.

Ultimately though, the Algors kept me warm and dry for hours in some pretty hostile conditions, enabling me to enjoy the views rather than complain about cold feet, so that is the main thing.

Value and conclusion

Some of my criticisms are based on fit and my foot/ankle shape which feels a little unfair - of all clothing, footwear is the one where fit is most important and subjective. Another rider might find them the perfect fit. As it was, the Algors didn’t cause me any actual problems and were warm and comfortable in cold conditions, which is their primary job.

The Algor retails at £230, and you pay £30 less for the Nubes without the Primaloft layer. This is at the lower end of winter footwear prices, yet they performed admirably in keeping my feet warm. This means that they must be considered reasonable value - there are many times when I would have paid a lot of money for warmer feet whilst out riding!

I feel a bit guilty only giving them 4 stars as a couple of my criticisms might just be my particular foot and ankle shape and they generally did their job very well. However, it is certainly worth being aware of these potential issues when trying them on.