Drag Pipes

Drag pipes are straight exhaust pipes, usually one per cylinder, running low and close along the frame with little or no silencing. They are a classic look on Harley-Davidson and other V-twin customs.

Without proper baffles they are very loud and change the engine's back pressure, so carburettors or fuel injection often need re-tuning to avoid a lean mixture, popping on the overrun and a loss of low-down torque.

In the EU, exhausts used on public roads must be type-approved (E-marked) and meet noise limits; open drag pipes usually fail roadworthiness inspection. Check homologation before buying an aftermarket exhaust.