Available in up to four sizes for a tailored fit, Quantum features great ventilation, excellent coverage, and of course Bontrager's signature out-of-the-box comfort and incredible ease-of-use. A removable visor adds to the value of a helmet that feels just as at home on the trail as it does on the road.

Features

  • In-mold composite skeleton allows a greater variation of vent shape and size
  • Micro-Manager - Fully-adjustable fit system fits a wide range of head sizes
  • Soft, comfortable, moisture-wicking and washable helmet pads
  • LockDown strap dividers - Helmet strap management made simple
  • Internal, recessed channels manage airflow through the helmet and over the head
  • Removable snap-on visor with visor port plugs
  • Crash Replacement Guarantee
Part No. Size Certification Color Weight
433029 Bontrager S 52 - 56cm CE, CPSC Adult Hot Green / Black 310g
433030 Bontrager M 54 - 60cm CE, CPSC Adult Hot Green / Black 340g
433031 Bontrager L 58 - 64cm CE, CPSC Adult Hot Green / Black 350g
433032 Bontrager S 52 - 56cm CE, CPSC Adult Red / White 310g
433033 Bontrager M 54 - 60cm CE, CPSC Adult Red / White 340g
433034 Bontrager L 58 - 64cm CE, CPSC Adult Red / White 350g
501174 Bontrager M 54 - 60cm CE, CPSC Adult Black 340g
501175 Bontrager L 58 - 64cm CE, CPSC Adult Black 350g
501176 Bontrager XL 60 - 66cm CE, CPSC Adult Black 360g
420391 Bontrager S 52 - 56cm CE, CPSC Adult Black 310g
420392 Bontrager M 54 - 60cm CE, CPSC Adult Black 340g
420393 Bontrager L 58 - 64cm CE, CPSC Adult Black 350g
420394 Bontrager XL 60 - 66cm CE, CPSC Adult Black 360g
501165 Bontrager S 52 - 56cm CE, CPSC Adult White 310g
501166 Bontrager M 54 - 60cm CE, CPSC Adult White 340g
501168 Bontrager XL 60 - 66cm CE, CPSC Adult White 360g
420395 Bontrager S 52 - 56cm CE, CPSC Adult White 310g
420396 Bontrager M 54 - 60cm CE, CPSC Adult White 340g
420397 Bontrager L 58 - 64cm CE, CPSC Adult White 350g
434467 Bontrager S 52 - 56cm CE, CPSC Adult Visibility Yellow 310g
434468 Bontrager M 54 - 60cm CE, CPSC Adult Visibility Yellow 340g
434469 Bontrager L 58 - 64cm CE, CPSC Adult Visibility Yellow 350g

Pro Sizing

Measure the circumference of your head using a cloth tape measure or a piece of string and a ruler. Use the chart below to find the proper helmet size based on your measurement.

cm 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66
  Small                  
          Medium            
                  Large    
                      X-Large

1 Head

Take your measurement horizontally across your brow and over your ears.

Ride it and love it. If not, we’ll take it back.

Ride it and love it. If not, we’ll take it back.

It’s that simple.

If for any reason you’re not satisfied with your Bontrager products, return the item - along with the original sales receipt - to the place of purchase within 30 days of purchase date for exchange or store credit.