Most of the tyres compared below are what you’d call ‘street-legal knobblies’. They work fine on dry roads as long as you remember what you’re riding, but some may give you a bit of a fright if you don’t, especially in the wet.
There’s no free lunch: road-legal knobblies wear faster than Road Touring or Do-It-All tyres – the reward is more secure grip on loose surfaces which may be more of a priority on your trip. It’s certainly less tiring to ride the dirt with tyres like this. Traction is OK on a dry road where there’s usually plenty to spare anyway, but at the cost of smoothness, noise, braking and perhaps, getting the pegs down. Up to a point modern ABS systems compensate for a knobbly’s reduced traction on road, but that won’t stop you sliding off a wet hairpin. I’d designate most of these tyres as 50/50 road/dirt use; they do the job on the highway and work better than anything else on the dirt, including sand and mud.
Tyres shown here include Continental’s TKC 80 on the Tenere, a discontinued Michelin T63 (replaced with Anakee Wild) on the fallen XRL, original Michelin Desert on the black Tenere, on the BMW Funduro a Pirelli MT21 Rallycross which has around since the 1980s, Mitas MC23 Rockriders on the WR250 (left), a Mitas E09 on the XR400 below right.
One time I spent the weekend in Wales with my WR on its original Bridgestone TW 301/2s (left) and expected the worst. Though they were at least eight years old they managed just fine in everything except perhaps wet grassy ruts. Not a single slide in 150 miles. And with a dense knob pattern they ought to last OK and made no noise that I could hear.
There are scores more examples of full-on, balls-out, off-road racing knobblies. But on a big, loaded travel bike their aggressive tread patterns with tall, widely spaced knobs will wear very quickly on loaded edges, causing cupping on the front (uneven knob wear, right) to give a horrible ride on the road, as well as gripping poorly and squirming (knob-flexing) on road bends. Knobs may even break off at high speeds when a tyre gets hot.
These tyres can work on a light and low-powered bike like the CRF250L left (Maxxis Desert) but Conti’s popular TKC80 as well as most of the tyres shown below have shallow knobs for just that reason.