Dunlop Sports K139
DUNLOP SPORTS K139
EVALUATION
Ask any seasoned off-road rider what front tire to use and the answer will almost always be Metzeler. No hesitation or second alternative is usually offered. And Metzeler's reputation is well deserved. Metzeler front tires have been the overwhelming choice of pros for longer than other tire manufacturers care to remember.
Now, there’s another choice. Dunlop’s new Sports K139.
We’ve been testing K139s on different motocross and enduro bikes for a couple of months, and we’re impressed. The K139s match or exceed the traction and control provided by a Metzeler and last longer!
K139s have been in the prototype stages for quite some time with guys like Roger DeCoster, Mark Barnett, Darrell Shultz, Johnny O’Mara, Frank Stacy, Rich Coon, Jim Gibson, Graham Noyce, Andre Malherbe, Jeff Ward, Mike Bell, Larry Roeseler, Bruce Ogilvie, Jack Johnson, Mike Melton, Terry Cunningham and Dick Burleson doing R&D and offering suggestions.
The K139 has a 4-ply rayon carcass with a tall aspect ratio (meaning it has a deep sidewall). The aspect ratio makes the tire work well in loose loam and sand while the race proven rubber compound, dual outer knobs and tall center knobs provide excellent traction on hard packed blue groove tracks. Because the K139 was designed as a multipurpose tire for both motocross and enduro, the sidewall is a rim saver design (meaning the tire rolls out over the wheel rim farther than a regular tire).
Dunlop makes some pretty far-out claims about the K139, and our riding has confirmed them! We’ve used the K139s in the Mojave desert, San Bernardino mountains, Baja, Arroyo MX Park, Saddleback MX Park, DeAnza MX Park, and for scores of trail rides that covered all types and kinds of terrain including nearly solid rock. Bikes have been a Suzuki RM465X, RM250X, Maico 490, Maico 250, RM125X, Honda CR450R, CR250R and Yamaha YZ465H. The K139 worked great on all the bikes and under most conditions. It holds on hard pack, doesn’t knife in sand and holds well in mud. Our only complaint is use in rocks. The profile (aspect ratio if you prefer), is a little shal-
low for high speed racing through rocks. A 3.25-21 Metzeler is deeper and puts the outside of the tire a little farther away from the wheel rim. A fast rider can feel the rocks against the rim when blitzing through a rock field. Even so, we only experienced one failure—a broken casing from smashing into a BIG rock at speed. And we doubt any tire would have survived the impact. The rock wasn’t the kind normally hit and it crashed the rider instantly.
Most tires that grip well and give excellent control wear rapidly. The K139 is an exception. Tire life is 3 to 4 times that of a Metzeler, 5 to 6 times the life of most Pirellis we’ve tried!
Dunlop wasn’t sure about the price of the K139 at press time, but they said it would be competitive with other 3-00-21 knobbies. The K139 should be available by the time you read this—see your dealer and give one a try. 88
