SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: http://read.uberflip.com/i/1525626
UNDER PRESSURE Bilstein’s New Shock Designs Are The Opposite Of Bypass Technology By Dan Sanchez Photos Courtesy Thyssenkrupp Bilstein of America Working well under pressure is something Bilstein has been quite good at. The company’s development of a high-pressure monotube shock revolutionized Baja racing in the early 70s. Most recently, the company introduced its Black Hawk Powersports Coil-Over shocks for UTVs. According to Steve von Seggern, Head of Marketing, Aftermarket at Bilstein, and Shane Casad, head of Bilstein Product Management, this technology in these shocks is the opposite of what typical bypass and internal bypass shocks operate in off-road. “Our latest shocks are position sensitive and feature our ZoneControl® CR, which operates like a coil-over, bypass shock, bump stop, and limiting strap, all in one shock,” says Casad. The new Bilstein Black Hawk UTV shock’s ZoneControl® CR is a three-piston design with position-sensitive damping, three compression zones, and two rebound zones. The ZoneControl® CR’s main linear piston is a 60 or 70 mm, a secondary piston is a Jounce Cut Off (JCO), and a third is the Rebound Cut Off (RCO). “The compression JCO piston plunges into a telescoping flask that creates a two-stage compression zone. This internal compression stop is tunable and can develop up to three times the amount of compression force compared to the main working piston,” says Casad. “At the top, a telescoping internal compression stop, JCO, prevents the shock from bottoming out. On the rebound side, there’s an RCO system that decelerates the spring and protects the shock from reaching full extension by engaging the secondary rebound piston with the internal rebound stop. So there’s no need for a limiting strap.” According to von Seggern, the Black Hawk design is perfect for UTVs as you only need one shock per wheel. “It’s the most technology you can have on one damper,” he says. “For racers and recreational UTV owners, the position sensitive ZoneControl® CR shocks provide greater riding comfort while offering exceptional bottom-out control. They are made from an all-aluminum design and feature a finned aluminum reservoir that dissipates heat and makes them lightweight.” “We went this direction in the evolution of our monotube design because running pistons by multiple ports requires more service,” adds Casad. “With Bilstein’s pressurized design, and having the multiple pistons and damping zones work to provide proper compression and rebound under any condition, it creates less heat and lasts longer. These shocks also offer huge adjustability. At the top of the shock is the JCO and we provide a 10-position clicker to adjust bump while on the external reservoir, there is a two-speed high and low-speed compression adjuster with up to 40 percent of adjustment. There is also a rebound adjuster at the bottom of the shock.” “The technology works especially well for racers by offering a superior range of shock tuning when compared to anything else on the market,” says von Seggern. “There’s no compromise between achieving the bottom out control you need and the ride comfort you want,” Casad added. “The shocks are velocity-sensitive and adjust to inputs to achieve a level of comfort without fear of bottoming out.” While other shock companies are focusing on electronically controlled tuning, that is currently not on Bilstein’s immediate line of focus. They know that “e-dampers” are an OE idea that needs to be highly integrated into the vehicle’s electronic control units. “E-dampers are being experimented with on many vehicles,” says Casad. “We’ve worked with OEs like Toyota in the Tundra and currently with Ram on the TRX and its active suspension system. But there’s only a moderate aftermarket demand, and from our marketing research, we found most racers didn’t want it.” For now, Bilstein’s Black Hawk shocks are available for various Polaris and Can-Am models, but according to von Seggern, they will soon be available for universal applications. For off-road enthusiasts with light truck applications, Bilstein’s B8 8112 suspension kit also features ZoneControl® CR consists of a coil-over shock with an external reservoir, and is are available for Toyota Tundra, 4Runner, Tacoma, and Ford Bronco applications. They will be adding Ram 1500, F150, and GM1500 ZoneContol CR applications soon. For more information, visit https://bilstein.com/en-us/ SJ