Advice & Guides Advice: How to make sure your helmet fits correctly
You'd be surprised how many riders wear a helmet that's too big for them. Here's how to tell if a lid really fits you...
1 Feb 2022
HJC F100 - Bios Yellow
Dual homologated AFC helmet with integrated sun visor, ventilation system and quick dry interior
DetailsRRP
£339.99
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Verified Customer Reviews for HJC F100
Ergonomic and provides Jet protection
29 Aug 2025 by Anonymous
Bigger than other XL helmets due to the big void at the front.
Style: Plain Matt Black
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Very comfortable, visor noisy when partially open
12 Aug 2025 by Steve B
Fits my head shape petfectly. I wanted a glip top without the "beak" for blood biking.
Good quality for the price so good value.
Visor rattles or it may be wind noise when cracked open for ventilation.
Like all helmets an intercom unit has not been thought about in the design.
Style: Plain Pearl White
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Nice Helmet
14 Jul 2025 by AL
For a P&J helmet the wind noise is not too bad, ventilation is good. The visor, sun visor and chin guard are really easy to operate on the move wearing gloves.
Style: Plain Matt Black
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Comfy and well fitting
08 May 2025 by Anonymous
For a P and J homologated helmet ,this one fits my size L head very well
Style: Plain Pearl White
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Description
Product Specification
Variants
Manufacturer
HJC F100 - Bios Yellow
- Advanced Fibreglass Composite shell construction
- Ultra-lightweight aerodynamic shell structure
- Highly impact-resistant
- Dual homologated (P/J): fully convertible full face / open face
- Pinlock ready HJ-45 visor with anti-scratch treatment provides 99% UV protection
- Front to back airflow: two intakes and one exhaust
- Micro buckle locking system
- Moisture wicking and quick drying interior
- Crown and cheek pads are removable and washable
- Glasses grooves accommodate eyewear
- Pinlock, chin curtain and breath deflector included
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