Specialized use varying foam densities to build a safer helmet. High density foam acts best to absorb hard impacts while lower density suits softer blows that may be scaled up in force during impact.
Specialized use an aramid skeleton structure to hold the foam shell in place. Aramid is a strong synthetic fibre very similar to materials they use in bulletproof vests. The frame created by the skeleton structure allowed Specialized to be more versatile when designing the shape of the foam. The large vents are an example.
Fortunately, I have not been involved in any head collisions while testing the Ambush so I’ll have to accept Specialized’s safety claims.
Fit and comfort
To be blunt, the Ambush is the best fitting helmet I have worn. The 360 degree retention system is a pleasure to use. It adjusts around the entire circumference of the head so when tensioned the system pulls away from the helmet to prevent any pressure or pinch points against the hard helmet shell. Conveniently, this also creates a space for additional ventilation.
The low rear coverage of the helmet means that Specialized have had to integrate the tension dial into the foam shell. The dial itself is precise enough to find just the right fit and easily adjusted while on the bike The length retention system at the rear is adjustable, moving up and down the back the head for a good fit.
The retention system is not only comfortable and adjustable, but it also performs well in its primary task - keeping the Ambush firmly in place on the rider’s head. Even on the roughest descents the Ambush remained composed without the swaying or bobbing feel I’ve experience with other helmets.
The padding inside the helmet is sufficient and serves its purpose unnoticed. At first inspection, I thought the padding may be a bit thin and flimsy. However, I have not seen or felt any unreasonable wear on the pads yet. The Ambush does come boxed with a replacement set of pads should my initial suspicions prove true.
Specialized have used Tri-Fix splitters at what is traditionally the Y-joint on the straps at the jaw and ear area of the head. The non-adjustable Tri-Fix splitters create a more rounded U-shaped joint. This creates more space for the ears and removes the second strap normally used in adjusting the placement of the Y-joint. The result is a hassle free experience in an area that often causes discomfort. However, not being adjustable, there is a chance that a few people might not fit as well as Specialized planned.
The Ambush comes with a number of vents designed to keep the rider cool. Specialized included channels inside the helmet to complement the incoming air. Although I missed out on the hottest parts of summer, the Ambush has kept my head cool at all times while not feeling breezy even on the coldest winter mornings.
The visor on the Ambush is adjustable. It is firmly attached on either side of the helmet and moves up and down a grooved channel. The range is good, allowing for the stowing of goggles when up, while getting low enough to defeat all but the lowest sunset. Adjusting the helmet while riding is a breeze as you simply pull or push it into the desired position. There are no problems with sunglasses as the brim of the helmet is relatively high in front.
All that said and we have not even got to the most impressive part, the weight. With the additional surface area, visor, retention system, and some of my sweat and hair, the medium Ambush on test weighed in at 296 grams. For those who have a life outside of bicycle helmet specifications, that is impressively light for an all-mountain / trail helmet.
The combination of the comfortable fit and light weight help you forget about the Ambush as soon as you clip-in the chin strap.
So what’s the catch?
After reading this glowing review, you might be wondering what doesn’t the Ambush have?
The biggest stumbling block for many people will probably be the number on the price tag. The Ambush is not going to please everyone’s pocket with a recommended retail value of R2,599.
There are no models with the MIPS liner which is supposed to assist with dangerous rotational crash forces. Nor is there provision for an integrated action camera mount. Goggle support could also be beefed up with only a slight peak in place to catch the strap slipping up and over the helmet.
In the end
The Specialized Ambush is the best mountain bike helmet I’ve worn. The combination of the comfortable fit, precise retention system, good ventilation, and the low weight are unmatched. It also looks good, with colour options to please most tastes.