Fast enough to cover ground. Composed enough for rocky, rooty British descents. ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏  ͏

Made for epic days on UK's natural trails
There's no rule that says every ride has to be bigger, steeper or more technical than the last. Our most memorable moments on two wheels often come from those plot a route and go rides that leave you with a grin even the thickest layer of mud can't hide (and this time of year, the mud is not optional). We designed Cortex to be the bike 99% of UK trail riders should be riding in those moments - whether you're planning a long all-terrain epic or flying round your local trail centre.
Customer favourite Cortex builds

Cortex Deore
£1,699 was £2,149
Customise
Cortex Eagle 90
£2,199 was £2,799
Customise

Mud season, sorted. Buy now. Deliveries from 13 February.
Explore Cortex
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Trail-ready kit for off-road days
Arro
"This windjacket lives in my backpack. Its the perfect layer for taking out with me on my mountain bike, running, or hiking. " - Becky
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Floe Gloves
"Amazingly comfortable. The gel padding is great and makes all the difference off road. I wear them in most weather conditions." - Ian
Floe Gloves

Vora 6L
For days when a rucksack feels like overkill, but pockets just won’t cut it. Carry the essentials while staying balanced and free to move.
Shop Vora
Skytrail 14L
For big days on the bike: a 14-litre MTB backpack built for hydration with a secure fit, breathable back panel and tool-specific pockets.
Shop Skytrail

Rent. Ride. Return. (Repeat)
Our full range of Sonder gravel, road, hardtail, and full suspension mountain bikes is available to test ride. You can rent a bike for a day, a weekend, or a week, and get your rental fee back if you choose to buy a bike afterwards. Plus, if you're planning a multi-day adventure, you can hire a full set of bikepacking bags too.
Try Before you Buy

How to Overcome Fear on Technical Trails
Technical sections can be the most exhilarating part of mountain biking - or the most intimidating. Sonder rider Lucy Allan show us how to build up confidence to riding mountain bike trails one step at a time.
Read Lucy's guide

Ride with us - join our winter gravel series
Sonder Winter Gravel series arrives at Alpkit Ambleside this Sunday 8th February. Join us for another community gravel ride, complete with hot drinks, snacks and good vibes. Post your photos from this season's gravel series and tag @Sonderbikes and @Smithoptics on Instagram for a chance to win a Smith helmet. Sonder demo bikes will be available to hire at each event.
Sign me up
See all the rides

Our Founding Principles
Outdoor Brand Of The Year 2026 TGO Magazine