Trek Ballista Mips: Helmet from Lidl-Trek with good ventilation
Trek no longer markets its clothing and accessories under the name of its subsidiary brand Bontrager; the Trek Ballista Mips should not be confused with the Bontrager Ballista, its direct predecessor. Even that one was aerodynamically optimized, but the current Ballista goes a step further. It's significantly longer at the back and doesn't extend as far over the forehead on a real head as it does on our dummy. It also sits at a lower profile, making it perfectly suitable for pairing with large cycling glasses.
Smooth but well ventilated
Two things stand out about the Lidl team helmet: For an aero road helmet, the Ballista is quite well ventilated, and given its flat construction and MIPS liner, it's also quite lightweight. The test sample in size L weighs just 270 grams, which is a top value these days—the era of superlight road bike helmets under 200 grams is over.
The Trek's aerodynamic highlight is the groove running perpendicular to the direction of travel, which is designed to direct the airflow around the helmet all the way to the rear edge. This is intended to reduce drag, saving over 5 watts of power compared to its predecessor. The four large vents also don't compromise the helmet's aerodynamic performance; they provide surprisingly good ventilation, making the Trek Ballista comfortable to wear even in warmer temperatures.
The head ring is not entirely convincing
For the head ring, Trek uses the BOA closure, familiar from cycling shoes, which allows fine adjustment in both directions (tight/loose). Furthermore, the head ring is height-adjustable to three levels, although the movable part of the retention system is so loosely connected that it comes off as soon as the helmet is removed and then has to be reinserted. Apart from this minor flaw, the fit of the Trek Ballista is impressive, and thanks to the MIPS inner shell for protection against rotational movements, safety should also be top-notch.
In addition to the striking team look, the helmet, which costs €299, is also available in black and white, as well as three sizes. A helmet bag is included, and even those who ride a road bike other than a Trek could find the Ballista faster.