Shinko off-road tires. From left to right: Shinko 504/505 tires for hard terrain; Shinko 524/525 tires for soft/intermediate terrain

Go to any track day with a sportbike, and it?s all about lap times ? and tires. There are supersport tires, racing slicks and race compounds, tire warmers and laboratory-grade pressure gauges, and mandatory tech inspections. Grip means everything ? and on asphalt that is better than any public road in the galaxy. Control, control, control.?? 

So what?s up with us dirt donks" A track day at the local MX park has no tech inspections, but the rough-and-tumble flyboys (and flygirls) go about their berm-slaying and seat-bouncing with equal zest to their roadie counterparts ? and typically with less focus on tires. Serious dirt guys and racers keep their rubber fresh, of course, but for us commoners, the adage is, ?If the knobs aren?t too worn, they?re good to go.? Just air ?em up, lube the chain, and hit it, Mitch.?? 
From left to right: Shinko 524 tire for soft/intermediate terrain; Shinko 504 tire for hard terrain

Well, I?m here to tell you that tires are just as crucial for dirt work as they are for the street or track. Old knobbies ? compromised by time, wear, and exposure to sunlight and ozone ? harden, losing their elasticity and ability to conform to the terrain. And with wear, they lose needed tread depth and the sharp edges crucial for gripping the infinitely variable and always changing Mother Earth.? 

En...