Inboard brake

Its main advantages are twofold: a reduction in the unsprung weight of the wheel hubs, as this no longer includes the brake discs and calipers; and braking torque is applied directly to the chassis, rather than being transferred to it through the suspension arms.

A rare few rear wheel drive racing cars (e.g., the Lotus 72) have also used inboard front discs, accepting the need to provide a front brake shaft to gain the overall unsprung weight and braking torque advantages.

The benefit of such a system is primarily the reduction of unsprung weight which improves handling and ride.

This greatly discourages their use in motorsport, and the additional time makes for greater labour cost when servicing these parts.

The Hummer H1 is one of the few modern vehicles fitted with inboard brakes, to accommodate each wheel's portal gear system.