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  • Bell Catalyst MIPS Helmet
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  • Bell Catalyst MIPS Helmet
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BellCatalyst MIPS Helmet
Sale 30% Off$104.98 - $119.98

Item # BEL00BX

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  • Matte/Gloss White/Gunmetal, S ($109.98)
  • Matte/Gloss White/Gunmetal, M ($109.98)
  • Matte/Gloss White/Gunmetal, L ($109.98)
  • Matte Black, S ($119.98)
  • Matte Black, M ($119.98)
  • Electric Matte Crimson/Black, S ($104.98)
  • Electric Matte Crimson/Black, M ($104.98)
  • Electric Matte Crimson/Black, L ($104.98)
  • Bluster Matte Slate/Orange/Coal, S ($104.98)
  • Bluster Matte Slate/Orange/Coal, M ($104.98)
  • Bluster Matte Slate/Orange/Coal, L ($104.98)
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Item # BEL00BX

Catalyst MIPS Helmet

While your friends go slacker, longer, and sloppier on their enduro beasts, you just watch and shake your head. You don't have a problem with enduro and its loud following, but for you, the smooth laps of an XC course have always been where you feel most at home. Wear your Lycra, your carbon-soled shoes, and your Bell Catalyst MIPS Helmet with pride whether you're at a start line or on an after-work training ride; you may get passed on the descent, but you know it's the climbs that count, anyway.

While you're dodging past struggling enduro riders on your favorite local climbs, the Catalyst's ultralight design and 18 vents will leave you cool and dry as you push through hard tempo efforts. Plus, a solid In-Mold shell pairs with MIPS to provide you with protection that you'll forget about when you don't need it. MIPS, or Multi-Directional Impact Protection System, refers to the now-ubiquitous Swedish technology applied to the Catalyst in the form of a thin inner basket. This basket lets the helmet's shell rotate independently of your head upon impact in an effort to absorb brain-damaging rotational energy created in certain crashes. Bell's FloatFit and No-Twist Tri-Glide straps give you ample opportunity to get the fit you need, so you can focus on holding your lead on the pack.

  • Stay safe and speedy with this XC-specific helmet
  • MIPS technology minimizes the effects of certain crashes
  • In-Mold shell dissipates impacts the old fashioned way
  • Wealth of vents keep you cool and dry during hard climbs
  • No-twist straps and FloatFit design let you customize fit
  • Removable visor lets you shave more weight on race day

California Proposition 65


This product can expose you to chemicals including Bisphenol A (BPA), which is known to the State of California to cause cancer. For more information go to

Tech SpecsSize
Tech Specs
Shell Material
Impact Foam
18 vents
Fit Adjustment
FloatFit, No-Twist Tri-Glide
CE EN 1078
Recommended Use
cross-country, trail
Manufacturer Warranty
1 year


4Forty, Annex, Catalyst, Drifter, Falcon, Formula, Hub, Sixer, Stratus, Super 3R, Super Air R, Super DH, Z20

Head Circumference

20.5 - 22in

(52 - 56cm)

21.7 - 23.2in

(55 - 59cm)

22.8 - 24.4in

(58 - 62cm)

24 - 25.6in

(61 - 65cm)

Full-9, Full-9 Fusion
Head Circumference

20.1 - 20.9in

(51 - 53cm)

20.9 - 21.7in

(53 - 55cm)

21.7 - 22.4in

(55 - 57cm)

22.4 - 23.2in

(57 - 59cm)

23.2 - 24in

(59 - 61cm)

24 - 24.8in

(61 - 63cm)

Head Circumference

20.1 - 21.7in

(51 - 55cm)

21.7 - 23.2in

(55 - 59cm)

23.2 - 24.8in

(59 - 63cm)

Lil Ripper
Head Circumference

17.7 - 20.5in

(45 - 52cm)

18.9 - 21.7in

(48 - 55cm)

Local, Span
Head Circumference

19.3 - 20.9in

(49 - 53cm)

20.1 - 21.7in

(51 - 55cm)

21.7 - 23.2in

(55 - 59cm)

23.2 - 24.2in

(59 - 61.5cm)

 S / MM / L
Head Circumference

19.7 - 22.4in

(50 - 57cm)

21.3 - 24in

(54 - 61cm)

 AdultWomen / Youth
Head Circumference

20.9 - 23.6in

(53 - 60cm)

20.5 - 22.4in

(52 - 57cm)

Sanction, Transfer-9
Head Circumference

18.9 - 20.1in

(48 - 51cm)

20.5 - 21.3in

(52 - 54cm)

21.7 - 22.4in

(55 - 57cm)

22.8 - 23.6in

(58 - 60cm)

Sidetrack, Spark
Head Circumference

18.5 - 21.3in

(47 - 54cm)

19.7 - 22.4in

(50 - 57cm)

How to Measure:
For best results, use a tape measure to measure around your head where your hat would fit comfortably.

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Assuming the visor is removable. How offensive does it look without? It seems like the Stratus, but is available in a color way I prefer to match team kit.

Hi Jeff, the visor is removable/replaceable so without it will indeed look similar to the Stratus, just with some holes the visor would pop into.

Not bad.

  • Familiarity: I've used it once or twice and have initial impressions

This is my first MIPS helmet and hopefully, I will never have to use its feature. The helmet fits well and is light and airy. Looks a little cheaper in person than I was expecting, but not too bad. The visor is a bit flimsy and rattles over rougher trails.

A quality lid

  • Familiarity: I've put it through the wringer
  • Fit: True to size
  • Size Bought: Medium

I've always been partial to Bell products through my nearly 30 years of competitive road, TT and off-road cycling. It seems I have more of an oval-shaped "Bell head," versus other brands with more rounded shapes. I bought this helmet to replace my ten-year old Sweep that getting pretty grungy and crispy. This is a high quality helmet with a great fit and understated good looks. My only small quibble is that the visor is not adjustable and has a tendency to flop down slightly over time or when bouncing through the rough. I solved the problem by affixing a tiny patch of Velcro hook-and-loop fabric behind two of the points of the visor at the contact point with the shell. Done. It ain't moving.

James...I'm about your size and considering this helmet. Is it weird to ask what your head circumference measures? Typically I wear Large but since you're wearing a Med, wondering if that's what I'd need as well.

Unanswered Question

Can the strap be adjusted side to side to keep the buckle centered under the chin? The Z20 strap is stitched in the middle of the rear of the helmet and cannot do this.