Fox Racing Mainframe Mountain Bike Helmet - MIPS Protection

Our review of the Fox Racing Mainframe Mountain Bike Helmet finds it best suited for riders who want reliable impact protection and all-day comfort without a lot of fuss. The single biggest reason to buy is the integrated MIPS impact protection system, which reduces rotational forces in a crash by absorbing and redirecting energy that might otherwise reach the brain. On top of that, the helmet pairs extended coverage with smart venting and a removable, washable liner so it handles both trail rides and daily commuter use.

Key Features

• MIPS impact protection: Reduces rotational forces in a crash by absorbing and redirecting energies and forces otherwise transmitted to the brain for improved safety.
• Extended coverage: Extra shell coverage around the back and sides provides added protection on technical trails and when momentum shifts unexpectedly.
• Optimized venting: Channeled, in-molded EPS construction promotes efficient cooling during long climbs and hot commutes.
• Removable washable liner: The moisture wicking liner is removable for cleaning, which keeps the helmet fresh after sweaty rides.
• Integrated fit system: MIPS-integrated fit reduces weight and delivers a comfortable, more seamless fit without bulky adjustment hardware.

Who It's For

The Mainframe is aimed at mountain bikers and commuter cyclists who want a lightweight, ventilated helmet with proven safety features. Riders who do frequent singletrack laps or urban rides where coverage and rotational protection matter will appreciate the combination of ventilation and MIPS integration.

People who need a super-lightweight race helmet with minimal coverage, or those who prefer full-face protection for aggressive downhill riding, should look elsewhere. This helmet sits squarely between everyday trail use and casual commuter needs rather than specialty race or downhill categories.

Pros & Cons

Pros

• Integrated MIPS reduces rotational forces, enhancing crash protection.
• Well-ventilated in-molded EPS keeps airflow moving on longer rides.
• Removable, moisture wicking liner is easy to wash and maintain.
• Extended coverage gives added protection around the temples and rear of the head.

Cons

• Not a full-face option, so it is not intended for aggressive downhill use.
• Sized for a comfortable fit but riders with unusually shaped heads may need to try before buying.

Specifications

Our Verdict

The Fox Racing Mainframe delivers a balanced mix of safety, comfort, and venting that makes it a smart choice for trail riders and daily commuters who value rotational-impact protection. It is good value for riders who want integrated MIPS and a washable liner without upgrading to a heavier full-face option.

Frequently Asked Questions

Does this helmet include MIPS?
Yes, the Mainframe comes with an integrated MIPS system to reduce rotational forces in a crash.

Can I wash the liner?
Yes, the moisture wicking liner is removable and machine or hand washable to keep the helmet fresh.

Is this suitable for downhill racing?
It offers extended coverage and good protection but is not a replacement for a full-face downhill helmet for aggressive racing.