Surly Truck Stop Bar Handlebar - 31.8mm Clamp 51cm Width 30mm Rise Aluminum BLKSurly Truck Stop Bar Drop Handlebar Aluminum 31. 8mm 51cm Black. The Surly Truck Stop Handlebar combines the benefits of a drop bar with those of a riser bar. Offering a variety of hand positions for comfort over the long haul it also features 30mm of rise for a more upright and relaxed riding position. With a clean aesthetic its a great option for taller riders looking for more rise and for bikes with a low cut steer tube. Lightweight aluminum