approved. Tube Type. Note: D606F front tire matches with D739 AT rear for desert riders. Tire Specifications: Load / speed index: 69R. Recommended rim size (inches): 3.00 (2.15, 2.50). Overall diameter (inches): 27.40. Overall width (inches): 5.28. Full Dunlop designed the D606 tire to be street-legal, but with an emphasis on aggressive off-road riding and great longevity. A full-depth tread pattern designed for rigorous off-road use yields excellent traction on everything from hard-packed fire roads to soft single-track trails. At the same time, the D606's tread compound is engineered for good highway wear and grip. 10% on-road, 90% off-road. D.O.T.