The chunky Kenda Big Block has been on my ‘tyres to try’ list for years, so when I set off for Morocco on my near-new 450MT last October, I arranged for a 140/80-18 (7.1kg) and 90/90-21 (5.2kg) to be dropped off in Marrakech, assuming the bike’s stock CSTs would not last long or soon degrade. I know John M from Rally Raid is a fan of the Kendas (below).
The rear is listed as 140/70-18, but I’m told this size is rare, so the 140/80 rear Kenda would be a bit wider, taller and probably heavier.

In the meantime, road and trail, I was quite impressed with the stock Cheng Shin (CST) Ambro 4s which bear a striking resemblance to the Pirelli Scorpion Rally STR.

With probably a 1000 miles left in the Ambros (above left) at around 4600 miles, I decided to get the Kendas fitted in Marrakech while I still had a chance to test them on the trail, before heading back home across Spain. Out of town, as expected they initially felt odd on the road, like new knobblies can do. That settled down, hummed a bit more than the CSTs on smooth asphalt, but later on the dirt they felt too stiff at 30-psi road pressures (like many tubeless tyres), spinning out when stalled on a steep ascent, for example. I dropped to the mid/high 20s, but there felt little difference on the rocky or gravel tracks. Some bends I’d slice through like a pro, others I edged round like like a junior MX-er on their first day out.

On a heavy bike like the loaded 450 (195kg wet + gear) it can be hard to get your flow on some loose, stony bends. Meanwhile, on the few bits of deep sand (rare in Morocco), I did notice the 450 tracked well once you’d disabled the traction control. That’s as you’d expect with big blocks, though I think is also down to the 450’s unusually good steering and weight distribution.

On the road the Kendas still gave their moments: Once back on bendy mountain roads in southern Spain, I wasn’t cornering the way I could on the Ambros. A lot of this must be down to knobbly-on-asphalt syndrome: some rough or grooved surfaces set the tyres shimmying, even in a straight line. I’ve been used to that for decades and you just ride through this, but on the bends was another matter. Are the Big Blocks a knob too far?

Riding damp, winding mountain backroads from Seville to Granada, I had a couple of slips and at one point was so sure both tyres were punctured, I pulled over to check. Both were solid as. It wasn’t icy but I thought maybe I’d ridden through some unseen, oily agri-slime, or the dealer service in Seville the previous day had whacked up the pressures. Both tyres checked in at the regular 30psi.
On other occasions I thought perhaps the rubber needed to warm up in the chilly morning temps. This uneasiness came and went right across Spain until I thought: I can’t sell this bike with these Big Blocks, even if they make the bike look rufty-tufty and purposeful. Whoever buys it is likely to be a road rider. Once back in the UK I fitted some Mitas E07s (below) and will flog the Big Bs.