Formula for the circumference of an oval

The circumference of fastidiousness


Here is why regular bicycle helmets, to some, make them feel look “dorky.”

The polystyrene EPS (expanded polystyrene) helmet was invented in the 70s and today more or less is still the same; a bulky, rock-hard, and rigid device that can protect your head in bike crashes.

However, today, convincing cyclists to ride with helmets is no small feat as we have become much more aware of how we look and appear to our friends and social circle.

To become looking like a dork from riding with a big and clunky polystyrene helmet is, to many, not an actable tradeoff for the sensible thing it simply is riding with a helmet.

So why is it polystyrene helmets always will make you look like you are wearing a too-big helmet.

First of all, polystyrene needs a certain thickness of approx 30 mm to be able to protect your head in the event of a crash.

Secondly, by nature, the EPS materials used in bicycle helmets are rock-hard and stiff. There is no flexibility or comfort in a naked bike helmet. This becomes a problem when various human skulls have to fit in. No two head shapes are the same, even if we look at only heads of the same size/circumference. This is simply the beauty of us humans; we are all unique and special.

The only way to solve this when different head shapes fit into a stiff helmet is to make the helmet larger and do all. 

Third, because of the hard and stiff polystyrene, there needs to be some soft padding added here and there inside the helmet to ensure a minimum of comfort and to make up for the different head shapes that now have to fit in the rigid polystyrene shape.

All this is why a head of, say approx 57 cm circumference ends up with an outside circumference of some 77 cm when wearing an EPS helmet!

This is one of the reasons why Newton-Rider has reinvented the bicycle helmet as we know it. 

We have developed the N1 helmet using new materials with the same protective abilities as EPS but ~40% thinner. The N1 is also semi-soft and adapts automatically to different head shapes and thus does not need extra padding.

The N1 helmet design creates a much sleeker profile on one's head with an outside circumference of only about 68 cm.

The above animation illustrates the considerable difference between the two concepts. The red presents an EPS helmet, and the green represents the N1 helmet and how it adapts to different head shapes because of its semi-soft pads and the flexible soft liner.

Last but not least, the N1 can fold to fit into a bag to further adapt to the lifestyle of modern urban commuters.

/the Newton-Rider team

January 15, 2023 — Ulrik Jensen