Piper Cubs are known for a lot of things, but good brakes arent among them, at least if were talking OEM equipment. Our pre-war Cub had the original expander tube brakes that, although rebuilt and well maintained, worked sporadically well at best.
Beringer Aero doesnt yet have an STC for the Cub, but a cost-effective solution is the disc brake conversion from Grove Landing Gear Systems, Inc. Yes, the Grove conversion knocks the sheen off that restored-to-the-original gleam, but ask me if I care. You dont really need a lot of brake when flying an old taildragger, but when you need it, you need it badly-for run-ups or countering an impending groundloop that the rudder has given up on.
The $859 Grove conversion kit dispenses with the ancient expander tube and friction pad/drums and replaces them with conventional steel rotors and calipers. The rotors are riveted to the original wheels and the system retains the individual master cylinders in the cabin. The kit includes everything you need except fresh brake fluid. While youre at installing it, it might not be a bad idea to rebuild the master cylinders, which will cost $35 each for diaphragms from Univair. But thats not to suggest this conversion is exactly cheap as J-3 stuff goes. Robbie Grove told us labor is typically six to eight hours, but our shop billed 16 hours for a total labor charge of $1440.
The system fits the airplanes tiny little wheels aesthetically and the performance is almost transformational, not so much for stopping the airplane as holding it on run-up or making a tighter taxi turn, which is sometimes useful.
With the exception of retaining the old automotive-style flare fittings, the Grove conversion uses standard brake parts, including modern composite pads. The rotor is steel, not stainless steel, so it will corrode a bit. But regular use will prevent that from being an issue.
One thing Im a little wary of is that Grove specifies that the copper brake line from the Cubs stock system loops in front of the wheel assembly, as you can see in the photo. This means that its exposed to any kind of obstruction on the runway and that an errant rock could damage it. Grove said this hasnt happened in the years he has been selling the conversion, but I see it as a small risk nonetheless. Find out more about the conversion at Groves web site: www.groveaircraft.com.