Mechanical vs. Hydraulic


Until now, the most powerful tandem disc brakes came with hydraulic fluid—a messy choice for enthusiasts who demand simplicity. Previous mechanical discs, however, were inherently inefficient. Specifically, mechanical designs from Hayes, Avid, Formula, Hope and Shimano produced braking through the asymmetric movement of a single brake pad. With these unbalanced designs significant braking will not occur until the advancing pad warps the disc up against the opposing fixed pad. Compared to the hydraulic discs from the same companies (where opposing pads apply equal pressure) the result was diminished braking power, uneven pad wear and poor modulation. While primitive mechanical discs were adequate for single bikes, even the strongest captains couldn’t squeeze a brake lever hard enough to skid the rear wheel of a loaded tandem.


At an international trade show Santana discovered a young company with a breakthrough design—the first bicycle disc with mechanical ball bearing actuation and balanced power. Since early 2004 we have assisted this small company—named Winzip—with development and testing. In the meantime, they received a patent for a mechanical disc with two powered pads.


Although Winzip has been delivering brakes for the past two years, their earliest calipers had a number of small problems. In short, their inspired design wasn’t yet good enough. The tandem version that Santana has helped to create has stronger internals, smoother ramping with additional bearings, advanced pads and improved lever response. Moreover, to keep things simple, our special version requires far less maintenance. Finally, Winzip’s new Tandem model (manufactured exclusively for Santana) doesn’t have any plastic pieces that can melt and fail. Spare parts? While Santana’s tandem specific brake comes with premium long-life pads, standard Shimano pads fit and work great, and can be purchased anywhere.


While others have matched the 8-inch dimension Santana pioneered six years ago, we moved on to develop larger and more capable systems. What’s so special about Santana’s big 10-inch rotor? First, because braking power is a function of a disc’s effective radius, the larger disc increases stopping power by 29%. Next, the rotor’s heat dissipation (and fade resistance) is improved by an even larger amount. Finally since this new rotor size is supported by a universal chainstay braze-on, any tandem with this fitting can be upgraded to Santana’s 10-inch solution.


While a disc at either wheel can prevent a disastrous blow-out, a front disc necessitates a dished wheel and a special-dimension fork. Additionally, the heat of a tandem’s disc brake caliper will destroy a carbon fork (a fate worse than a blow-out). While front discs are the best choice for an all-terrain tandem with a suspension fork, the ultimate combination for a road tandem is a carbon fork and powerful rim brake up front, plus a capable tandem-rated disc in back.


Understanding Braking
Power vs. Heat
Disc Brake Technology
•••Mechanical vs. Hydraulic
Avid Brakes
Hierarchy of Braking Power