Behind the scenes at standardsetting British brake firm, DP
Each time we brake in the wet we owe a debt to DP Brakes, the UK’s sole maker of sintered pads
Disc brakes first became popular on bikes in the mid 1970s, but the new technology had a problem: disc brakes didn’t work in the wet. “Remember the Suzuki GT750?” asks DP Brakes’ Technical Director, Frank Edwards. “It had a sticker on the tank warning the brakes could be impaired in wet weather.” So the Government tasked the Transport and Road Research Laboratory to find a solution. “The organic pad compounds of the time didn’t bite through the water on the disc, they just aquaplaned,” says Frank. “The TRRL contacted Dunlop, who supplied sintered metal pads to the aviation industry. They made some for a test bike and they worked.” Sintered metal pad material is a blend of very specific metals, binders and friction modifiers that heat up, trap and evaporate the water from the disc surface, allowing pad-to-disc contact, even in the wet. ‘Sintering’ is the high temperature, high pressure manufacturing technique that forms the pad material into a stable ‘compact’ (the pad), and binds it irrevocably to the backing plate. Following the breakthrough, a new division was set up at Dunlop to develop the technology for bike use, involving Frank and his colleague Phil Ayliff and in 1978 the first sintered metal pad was launched, called Dunlopad.
“But at the time it was still only a small market for disc brake bikes,” remembers Frank. “So Dunlop sold the business to Phil, and Dunlopad was established as an independent company in 1983, buying pads from Dunlop but finishing, packaging and selling them ourselves.”
By the mid-1990s, supply issues meant the company needed to manufacture their pads themselves.
The company name was changed to DP Brakes (to avoid confusion with tyre sponsors), and a new plant was built and fitted with manufacturing equipment. That included a custom-built vacuum oven which simultaneously heats the pads to up to 1000°C and compresses them with a hydraulic ram.
Since then, DP Brakes have quietly grown into a global business, with 90 per cent of their output of brake pads, brake discs, clutch kits and gaskets going abroad, under a variety of brand names. They’ve captured key markets such as motocross and, in contrast, HarleyDavidson (the road versus off-road pads business is around 50:50). DP Brake-manufactured pads are favoured by Harley owners because of two unique characteristics: they’re quiet and they don’t generate brake dust. “They keep the whitewalls, white,” smiles Frank. Today DP Brakes employ 16 staff at their compact Nuneaton plant, and has the capacity to manufacture over half-a-million brake pads a year. “We’re a small company,” says Frank. “We don’t get heavily into race sponsorship or make a big noise because we’re so busy and we’d rather have strong sales.”