Pirelli MT21 Rallycross Rear Tires
This tire came stock on my 2014 KTM 690 Enduro R.
When it was new (< 300 road miles) it stuck like glue in slightly moist dirt, even if I didn't air it down below road pressure (26-32psi). I would say it hooks up substantially better than comparable dual-sport tires and it lives up to its 90/10 dirt/road claim.
It also performs quite well on the road *in good conditions*. The tire is quite soft and sticks to the pavement very well for such a knobby tire - I found myself scraping footpegs when leaning over very gingerly in smooth, dry and friendly-cambered twisties. That said, the contact patch is quite small. Therefore, if the road is wet, cracked and/or rough and you happen to pass over a small imperfection while leaned over (a painted line, a small crack, etc.), the tire will start to slip out from underneath you. With the rear, this isn't a big deal - but it's pretty scary when it happens on the front!
This would make a *terrible* commuting or "adventuring" (highway miles) tire. It howls at 40mph+ and it just doesn't last very long on the road.
I have almost 1,000mi on these tires, roughly 70% of which were on pavement and 30% on dirt, gravel, mud and sand. I have only run them at as low as 22psi once, and it was for about 10 miles of technical offroad trail-riding - they work so well at stock pressures that I haven't bothered airing them down since.
It comes as no surprise to me that the rear is looking very spent indeed, and it doesn't snap in the dirt like it used to. Even for casual trail use, it will beg replacing sometime in the next 500mi. However, for the moment it's still very useable on-road and off as long as you're not in a crazed race-fed hurry. Believe it or not, I actually had some fun in the soft sand today, where guys with more road-oriented dual-sport tires were getting stuck and frustrated. The front looks OK to go another 1,000mi.
So this is a fun tire, to take out on sunny days on nice roads and on moderately challenging trails. Don't expect to commute economically on it and don't expect to win any serious races - and it won't let you down.
June 15, 2014
Good for it's purpose
This tire comes standard on the KTM 690 Enduro R. It's a good 90/10 tire. It will come as no surprise that this tire has terrific manners off-road. It's nearly as good in mud as a full-on dirt tire. It's a little skittish in sand and off-camber situations, but that could be because of the 690's additional weight. I'll know better once I've compared some other tires on the bike.
It has better road manners than it's tread pattern would imply. It's a neat trick, but it comes at a price; the softer rubber doesn't fare well on slab. My tire is nearing the end of it's life after just 2000 miles. The front tire (another MT21) is hardly worn.
Granted, I spent more time on road than off. If your dedicated use is TRULY 90/10, then this tire might be a great option. I may continue with the MT21 on the front, but out back I'm gonna explore other options--probably the D908 or the Heidendau 60.
June 8, 2014
Great off road dual sport tire
This went on my DR650. It rides well on and off road. I won't hesitate to run another one. I paired it with a D606 on the rear and it's a great combo. After 2500 miles the rear is shot, but this front is only about 2/3 worn. It's starting to cup/feather so I may flip it around an see if I can squeeze some more life out of it. If not, oh we'll, for the price I don't feel it owes me anything.
June 4, 2014
Great tire so far
I have had this tire on my BMW F800GS for about a month now and a few hundred miles. On the pavement the tire works good, in the loose rocks it hooks up nicely, the mud it grips well. The wet grass it was a little loose but eventually digs in nicely. So far it has been a great tire.
May 12, 2014
Nice aggressive dual sport tire if dirt traction is key
Be sure to set front PSI lower than rear such as 18 psi front and 22 psi rear for street riding or else front tire will feel nervous. Handling on road is much better than most 90% dirt tires and turn in is smooth and handling is secure when leaned over. In the dirt these are much better than Trail Wings or other OEM rubber that most dual sports come with. On my XR650L the MT21s handle dirt well. No DOT tire handles mud quite as well as full on dirt tire but these are close enough and tread wear is fine unless you are a highway commuter.
June 13, 2011