
Helmets
New and used mountain bike helmets from UK sellers. Full face, open face trail, and park/dirt lids from Fox, Troy Lee Designs, Bell, Giro, POC, Smith, IXS, Leatt, Met and more. The most important piece of kit you own.
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MTB Helmet Buying Guide
Your helmet is the one piece of kit that isn't optional. Every ride, every time. Modern MTB helmets are lighter, better ventilated and safer than anything made even five years ago — MIPS, WaveCel, SPIN and other rotational impact systems have genuinely improved protection.
Helmet Types
Open face (half-shell) helmets cover the top and back of the head with an extended rear that protects the occipital bone. They're lighter, cooler and less claustrophobic than full face — the standard choice for trail, XC and all-mountain riding. Full face helmets add a chin bar that protects the jaw and face. Essential for DH racing, bike parks and aggressive enduro. Convertible helmets (Bell Super DH, Giro Switchblade) have a removable chin bar — climb in open face mode, clip the chin bar on for the descent.
MIPS and Rotational Protection
MIPS (Multi-directional Impact Protection System) is a low-friction liner inside the helmet that allows the outer shell to rotate slightly on impact, reducing rotational forces on the brain. Most premium helmets now include MIPS or a comparable system (POC SPIN, Leatt Turbine). It adds £10-20 to the price and is worth it — rotational brain injuries are the most common type in cycling crashes.
Fit
A helmet should sit level on your head, snug without pressure points, and not rock forward or backward when you shake your head. Size is measured by head circumference — most brands offer S, M, L with an adjustable retention dial for fine-tuning. Helmet shapes vary between brands — some run rounder (Giro, Bell), some more oval (POC, Smith). If a helmet creates pressure points, try a different brand before going up a size.
Buying Used Helmets
Only buy a used helmet if the seller confirms it hasn't been crashed. The EPS foam liner is designed to crush on impact, absorbing energy — once crushed, it doesn't spring back. A helmet that's been in a crash may look fine externally but have compromised protection. If there's any doubt, buy new. Helmets also have a recommended replacement interval of 3-5 years as the EPS degrades with UV exposure and sweat.
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