MT-21 Pirellis- Anyone tried them?

I'm looking for feedback on the Pirelli MT-21's. I mounted a pair for Pikes Peak and am unsure as to what I think about them. They sure are skinny but rumor has it the compound works great. So, if you have ran them before, let me know what you think. (I'm not wanting advice for other tires, I only want what you think of these)

Roostn in Golden

Well, didn't think too much of them in NH. The front would wash out and the rear not to good in sand or mud. I think on hardpack they would be pretty good though and probably last too. I have 1400 miles on mine and they are still in good shape ...but a lot of that was on the street. If you go for them, they run small so order 1 size up from normal.

- Sean

The MT-21 rear tire didn't work well on my WR. Very difficult to get the rear to slide smoothly. The rear tended to step out suddenly when dialing on the trottle in turns. The rear would finally hook up but the bike was really sideways.

A friend with a Suzuki RMX 250 had the same complaint about the MT-21 rear tire.

The damn thing will last for ever. Extemely long wearing tire.


Old guy, Dual Sported 98 WR 400 and GPS geek


I've been really pleased with the performance of my MT-21's, though you really need to look at what you intend to put them through. If you need a tire that can be considered street legal but still rip off the road this is one of the best you can get. The rubber compound seems to be quite hard which gives great wear, but probably sacrifices some off road. I researched the same issue before buying and it seemed there were different needs based upon where you lived. The guys on the east coast prefered someting different than the guys on the west coast. Since you already have them, I think you should wear them out and keep us posted. :)

Keep Roostin


I have been told that d.o.t. approved is only a recommendation of what kinds of tires they think are safe on the street.

There is no law (in Ohio) that states anywhere about what kinds of tires you may run on the street. (Except studded tires).

I took my bike (with s-12s on) to be inspected at the state highway patrol and was givin that info.

No one has ever hassled me about my s-12s

they don't wear very well but who cares.

I prefer to sacrifice performance in the street compared to the woods.

Ohio is a muddy place your conditions may be different.

They are a bit scary in the rain on the street.

3 rear tires a year $210

2 fronts $120

well worth it

p.s. yes I have tried mt-21s, and sold them in a week :)

I used to run MT21's on my XR650L. Yes, they are street legal. Yes, they are better than the stock dual sport tires.

But I used to chunk off the knobs of the tires. One time KerryT and I had brand new MT21's on our 650's. We chunked off the knobs and trashed the tires in just one narly, rocky ride here in Colorado.

I called Baja Designs and told them about our problem. They recommended a tire that isn't DOT approved but they said lasts longer than the MT21's and doesn't chunk AND is a true off road tire. The Bridgstone M78's. I've been using them ever since. Baja Designs told me they aren't DOT approved simply becuase Bridgestone never got around to attemping to get the rating. I don't know if that's true or not.

I have never been hastled for not having a DOT tire here in Colorado. In fact my old neighbor was a cop and didn't even know that was a requirement in Colorado.

I agree it depends on what terrain you ride and which state you live in.


Thanks for the input. I will basically only use them during the Pikes Peak Hillclimb and then go back to 756 Dunlops. The road is a super hard packed gravel that can get tacky with moisture. The cars clean it off pretty well and can literally blue groove it like a dirt track. No rocks or whoops. 2 miles of patchy concrete. I think they will work OK, I ordered a Goodyear Dirt Track tire just in case for the rear.


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