new product

The Rise of The Sentinel

Next Level DH Mountain Bike Helmet Design with Stephane Dion




We are super stoked to announce the release of our new mountain bike full-face helmet. Want to know how the design came about? Product designer Stephane reveals everything here.

AUGUST 4, 2021

The Sentinel is TSG’s newest full-face helmet, built for next level downhill mountain biking and jump sessions. Sleek, super vented and offering maximum protection in all conditions it was created in collaboration with one of the industries most legendary designers, Stephane Dion.

So who better to share the helmet’s back story than Stephane himself.

Stephane Dion Helmet Designer

The designer in his working environment.

I. The Helmet Guy

Stephane’s relationship with TSG was a coincidence, starting with a chance exchange of ideas at the 2019 Milan Motorcycle Expo about a DH skate helmet. “We left it there,” explains Stephane, one of the most experienced helmet designers in the industry”, and only talked again as the pandemic was taking hold of the world about a totally new project for a downhill bike helmet.” As the old axiom goes, every cloud has a silver lining, and with Stephane in lockdown and a snowmobile helmet project on ice, he had the opportunity to get busy on what would become TSG’s newest MTB DH helmet, the Sentinel.

I wanted to create a style

that was dynamic

Stephane has been designing helmets for over 25 years but mainly for power sports like snowmobile, street and MX bikes and even skydiving helmets. He is also really into FMX and enduro motorcycles, with one of his sons racing 450 MX and competing in DH mountain bike, he also knows a thing or two about downhill bike helmet design.

Stephane Dion Helmet Designer

Stephane checks the best peak position.

II. Following a typical German Swiss product design philosophy

“First I had to immerse myself in the downhill bike world to see what the competition was up to,” explains Stephane of his process. “TSG have Swiss, German roots so I wanted to create a style that was dynamic and fast looking but also expressed technicality and functionality typical of German and Swiss engineering.”

a typical German Swiss

product design philosophy

One of the key characteristics that the Sentinel should have was durable, “again a typical German Swiss product design philosophy,” Stephane says. “We also needed to get the proportions spot on: The chin bar not to far out; the correct amount of Goggle space in the eye port area; the perfect peak position and collapsible features to help reduce breakage in crashes.”

TSG Sentinel Helmet

Detail view of the front chin bar ventilation.

III. Weight and ventilation are top priority 

The helmet would also have to be easy of getting in and out of and hit the set 1150g weight target, as although the ‘pedal to the metal’ part of downhill biking only happens in short spurts a rider ends up wearing their helmet for hours which is a burden on neck. “The weight of the helmet is sitting on the highest point of the body and on hard breaking down steep inclines it takes very little to flip,” adds Stephane. “Every ounce saved helps keep the back wheel on the ground and so the top of priority is weight in every helmet I design.”

Ventilation was also a top priority: “For a helmet with this much coverage the air circulation – even at low speed – has to be on point, so the helmet has an elaborate channelling system with multiple ram air and exhaust vents front side back and top,” Stephane explains.

TSG Sentinel Helmet

Details rear view of the Sentinel Helmet.

IV. Thinking environmental

TSG also had an environmental target to fulfil and therefore an injection shell made from ABS material was decided on, as these materials can be recycled simply by placing them in the correct bin. Also, although the topcoat of an injected shell helmet uses chemicals paints and clear coats by avoiding epoxy primers it saves on processes that are harmful to the environment.

TSG Sentinel Helmet

The outer shell is made of ABS what is less harmful to the environment than fiberglass.

V. The Sentinel ticks all the boxes

Stephane describes himself as a “the helmet guy”, who at 53 years old still practices helmet design in an old school way. In his own words he takes responsibility for every stage of a helmets design, from concept and styling to production and brings in the best of the best, like in CAD, to help to make the process perfect. Stephane also believes that having a relationship with a factory is a key to the success of his methods: “The Sentinel is in the very capable hands of a small factory who do only high-end quality projects and I have my coffee mug with my name on it hanging there with the rest of the employees.”

TSG Sentinel Helmet all 2021 colors

2021 color range of the Sentinel helmet.

To wrap up Stephane says, “TSG wanted to offer a high-end downhill helmet at an affordable price and they have achieved it hands down”. Check out the Sentinel, available in satin black, satin red, satin olive, and satin grey, on the and at all good bike shops. And the next time you’re pointing a bike downhill, shoot Stephane a virtual high-five for the Sentinel that’s keeping your head in one piece!

Thanks Stephane!

Shop the Sentinel now