Gear Reviews

509 Allied Mono Suit Review

Growing up in Pemberton, we had some of the most beautiful mountains in the world in our backyard. My parents are avid skiers and had me on the hill before I could walk. People used to ask my parents how they got their kid to play in the snow for such long periods of time.

Their answer was simple: proper winter gear.

The same wisdom applies just as well to adults who want to stay warm, dry and comfortable while they push the limits of where they can go, in every weather condition. Proper winter gear.

With that in mind, here is my 509 Allied Mono Suit Review.


509 Allied Mono Suit Review
8.4 Comfortable, Great Value
The 509 Allied Mono Suit is super comfortable, and at half the cost of some other mono suits, it's got great value. And it looks sharp too!

509 Allied Mono Suit Review

509 Allied Review
Joel Poggemiller

Working at Innerspace Watersports in Vernon, BC, I was offered the opportunity to jump on a snow bike last season for the first time. I was immediately hooked.

Throughout my first season I wore my normal ski gear, only to find snow sliding up my back every time I bailed. I learned very quickly that I need the right equipment to keep me warm and happy out there.

So I decided to get some proper gear that would allow me to take my riding further. I chose the 509 Allied Mono Suit to ride in this season.

509 Allied Mono Suit Review-4
Josh Stack

Things I Love

Not only does it look great, but I am comfortable and warm no matter what conditions are thrown my way. Here’s what I love about this suit.


First up is comfort. I’ve done a lot of different activities this winter, from digging people out during my AST1 course to taking the snow kayaks out in my backyard and, of course, all the epic riding days in the mountains around the Okanagan. Through it all, this suit has been the most comfortable piece for every activity. It moves with me. I love the high zips and the thumb holes and the hood size and the fact that it fits over my helmet. I can’t wait to put my onesie on and go play. It feels exciting to get geared up. I give it a 10/10 for comfort.

509 Allied Mono Suit Front
Scott Chisholm
509 Allied Mono Suit Back
Scott Chisholm

Bang for Your Buck

As a noobie to the sport of snow biking, I wasn’t sold on spending $1100 on a mono suit. The 509 Allied is half the price of some other brands, and so far I am really pleased with its performance. For value, I will also give it a 10/10.


Thoughtful placement of vents, pockets and zippers is a huge factor to consider in making an outerwear purchase. If I am struggling to get things out of my pockets, or snow is coming in my non-mesh-lined armpit vents, I am not going to be happy. The 509 Allied Mono Suit feels like a rider designed it with riders in mind. The armpit vents and thigh vents are all mesh-lined, as they should be.

509 Allied Mono Suit Review-5
Josh Stack


The pockets on the Allied are easy to get to, and the media pocket is hands down my favourite thing about the suit. I am the kind of person who will forget to zip-up from time to time, but the media pocket is deep enough for my phone to slide right down inside with little risk of falling out. As a backup, heavy-duty Velcro ensures that nothing is coming out, even if I forget to properly zip-up the pocket.

I love that the media pocket is on the outside of the suit for those times when my riding buddy is about to hit a gnarly cliff with little warning. I can grab my phone to get the shot much faster than having to unzip my suit to get to an inside pocket. I just have to remember to wear my transceiver at least 20 cm away from my phone pocket.

509 Allied Mono Suit Review-6
Josh Stack

Boot Zips

I also love the convenience of the boot zippers! They make it so easy to put the suit on without stretching the material over my Klim boots.

But also, if I unzip the boot zips all the way, I can sneak my kneepads on from the bottom. That way I don’t have to put them on until the last minute, and I can load, unload and drive around town in comfort.

509 Allied Mono Suit Review-9
Josh Stack

Room for Improvement


I am a 5’4”, 125lb woman riding a man’s suit. I have a size small, but after riding it a few days I have discovered than an extra small would have been a better size choice for me. Because of my smaller frame, I had to remove the suspenders because they made the belly of the suit bunch up when I had the straps where I needed them to be comfortable. For sizing I would rate the Allied Mono Suit an 8/10.

509 Allied Mono Suit Review
Scott Chisholm

Convenience Zip

Any lady that rides, skis, tours or does anything adventuresome in the bush knows the struggles of doing your business in the snow. Carefully removing the arms and pulling them through the knees—all the while making sure the inside of the suit does not get snowy—is quite a process. The mono suit is great for guys…but let’s face it, even men have to do the deed in the bush from time to time.

A butt flap—or as one may put it, the convenience zip—would be highly appreciated in the Allied Mono Suit. For that reason, the suit loses some convenience points for me here. 7/10.


The outside of the suit has remained weatherproof in all of the Okanagan riding conditions I’ve experienced this year. I’ve been out in freezing rain, blower pow and, of course, bluebird days, and I’ve remained warm and dry throughout.

A situation to consider would be enduring multiple days with freezing rain or wet, heavy snow conditions. We mostly get champagne powder in the Okanagan, but I think the waterproofing might struggle on multi-day excursions or for people facing constantly wet snow conditions. By the end of each day of riding I was dry inside still, but the outside of the suit had to be dried out by my fire each evening to make sure it was ready for the next ride. 7/10 for waterproofing.



  • Comfort
  • Weatherproof in the Okanagan
  • Price
  • Convenience of pockets, zips and ventilation


  • No convenience zip for women
  • Weatherproofness in extremely wet snow or multiple days riding
  • No lady-specific sizing

– Brooke