pirelli mt-43 trials tire..DOT yes!

Defiantly interested in something like those trials hacks!

That's a P rated (93mph) tire with max inflation of 33psi. This shouldn't be happeneing in a couple hundred miles no matter if its street or offroad. Granted the tire isn't specifically pproduced for street use. Id be curious of the manufature date of both tires that failed.

Also..... heating suggests underinflation not over.

Everything in this thread says run it at 13-20 psi on the road.

Quote- boatman "Also..... heating suggests underinflation not over."

Overinflation will make the tire run on a skinny contact patch heating up just that part of the tire. (the center)

Underinflation will spread the friction over the whole tread area, warming the WHOLE tire up gradually.

The knobs on the MT43 act as fans, there is well over twice as much surface area to dissipate the heat created from running lower pressures.



The ripped knobbs were likely from overinflation heating up the center, then hard braking possibly is what ripped them off when they were near molten.

Knob tearing is in acceleration direction
The pressure run is wirh the manufacturers spec. Many others jave run it in the 20psi range wirhout chunking

The middle knobs on my mt43 are all boogered up as well but that is from them rubbing on the mud flab of my old husky. I'll have to take a picture of the tire but it looks like there's an outer covering of the knob and that's what's coming off.

The tops of the centre knobs got trimmed by the front of my swingarm. The tyre is still going strong after 16 months now.
8-12psi. Probably just over half worn...

What speeds are you running at those psi's

The pressure designation on the sidewall only pertains to the load capacity and shouldn't be interpreted as a recommendation unless you are loading the tire to that capacity. It seems reasonable to expect the tire not to self destruct because of that pressure though.
If you still want to use that tire for your application after two failures I'd recommend contacting Pirelli and discussing it with a tech. Pirelli here in the USA has techs that are responsive and helpfull. www.us.pirellimoto.com

If you wouldn't mind sharing just what your application is, It would be a good contribution to this thread.
Good Luck

The lines in the center knobs are worn away, and the hairs are intact still on the outer part of the second row of knobs.

I think that pic, simply shows you were running with pressures that are way too high.

Like I said above, too much air in the tire left the center knobs to take all the friction and develop so much heat that they failed.

Quote(Kenny61)
"tire pressure on the last one was 22psi. cant remember what the psi on the first one was but I know it was at least 22 and was most likely around 25-28psi"



Tire testing is done under load, that tire was able to withstand the testing at 33 psi because the entire tire was subjected to a load. They push it down onto the dyno with 617 pounds of force and roll it for a certain amount of time at a certain speed.

It says those # on the side of my tire. I'm not sure of the testing procedure but i think it's basically what I outlined above.

Just because it says 617 pounds at 33 psi doesn't mean a 263 pound load at 28psi is going to be fine. There's a thread on this topic.

http://www.advrider.com/forums/showthread.php?t=774699



And found this post to further explain my point on manufacturers "max psi"

I have a friend (ex-pro dirt track racer) that uses this tire regularly on his 950 Super Enduro, pressures in the +20psi range and hasn't had this issue at all. What I've learned over the years (many years) is lower pressures create more heat because of the tire flexing more. I've had plenty of tires chunk off because of underinflation and a couple due to overinflation but that was running them at max psi.

I've run quite an array of pure off road tires and DOT tires on the SE, psi's from 8-38 and never had this issue.

An XR650 running at 22 psi shouldn't be doing this.

I run 8 psi in my MT 43 all the time. Pavement, dirt, or true dual sporting. I've never observed the poor handling issues others reported at various (mostly higher) pressures. UHD tube. Two rim locks. No issues. No knobs falling off, no wallowing on the road. Just don't break traction and the bike keeps moving forward.

Quote: An XR650 running at 22 psi shouldn't be doing this.

Agreed... I guess he could have got a bad tire. (the second one).

Or has an inaccurate tire gauge, or just guesses how much air it has in it.

That's what it sounds like;

"tire pressure on the last one was 22psi. cant remember what the psi on the first one was but I know it was at least 22 and was most likely around 25-28psi"

Really? Just guesses? Sounds like your just guessing at what may be wrong. Ive used 3 different gauges just in case one was wrong. This tire was at 22 psi the one before I simply dont remember because it was 7 weeks ago that I filled it up. I usually run 18 lbs in a T-63 but uppped the pressure to get some longer tire life which is what many people recomended when I tried the MT43. Are you even running one? how many psi do you run it at? or are you simply just throwing out wild ass guesses as to what you think is going on. The manufacturer has rated the tire at 33psi and 90 mph. The owners manual calls for 22psi. It was warrantied with the info given.

Thanks I was planning on shooting off an email but just wanted to get some feed back from other users first

Allright, I was guessing what you had for a tire gauge. Sorry for that.

Not guessing that you overinflated the first one. Its clear you did, you said 28psi.

Like I said, perhaps you got a bad tire.

If you inflate a new 18x4.00 MT43 to 16 psi, it won't wear like yours did, and it won't throw knobs. That is the best solution.

The max psi is for testing purposes only as outlined by me above, and by "lamotavida".

It's a shame that the manufacturers don't stamp that on the tire as Avon did on my rain tire.

If you go thru this rather short thread, you will find most are running it at much lower pressures, in the 12-16 psi range for pavement.

Yes I'm running one, this from directly above your first post;

I hope you pick up another one, I really do, as it's a great tire.

Thats what I was looking for, Thank you.

I was running 10 psi with a heavy duty tube on my husky for woods riding, dual sporting. The tire would definitely grow taller at speed which caused it to rub like crazy on the mud flap.
I'm going to put the mt 43 on my 350 this week. I just bought a new chain to get the tire away from the swingarm. I don't want rubbing on the swingarm.
How much room do most of you have between the tire and the swingarm without getting it to rub?

I rode my G450X to Snow Shoe for the GNCC and then I took the long route home. The trip worked out to just under 800 miles in four days on a new MT 43 rear. My pressures varied from 13 to 20 psi depending on road surface and speeds up to 70 miles per hour on pavement. The Pirelli performed great with no chunking.

So do any of you that are using this tire on the road at higher speeds balance your wheel? If so how much weight has been needed.

Where did you get that? I couldn't find a recommended pressure on there web site & never got a response from an email to them.