Nitrogen Bumpstops - Kopycinski's Brain
Keep Your Suspension Protected
Pressurized nitrogen bumpstops (often called air bumps) are the ultimate protection against hard bottoming your suspension and slamming parts metal-to-metal. Rubber and polyurethane stops are effective for casual off-road driving and slow suspension action where you just need to limit up-travel. But when running at high speeds or consistently pushing the suspension near full compression points, nitrogen bumps rule.
A cylindrical nitrogen bumpstop is essentially a short-stroke pressurized shock. It uses oil flow through internal orifices to dampen, or slow, the suspension movement during its final few inches of travel. They typically exhibit some rebound damping as well, so the suspension moves back to extension faster than the air bump, and the bump does not apply active pressure back onto the suspension.
We consulted with Mike Leighton at King Shocks to better understand some of the technical details of choosing and using nitrogen bumpstops. King offers both 2- and 2½-inch diameter body bumpstops. Size and weight of the vehicle determine which diameter bump is needed to provide the appropriate level of bottoming protection to control the suspension.
Like most suspension components, choosing the right parts up front is important, but tuning the working package is where you really get the best performance out of the system. This holds true for nitrogen bumpstops as well, as they have a number of variables that can be adjusted to dial in the right behavior.