Is anyone running a Pirelli MT 43 Trials Tire with stock gearing?? I ran one on my 09’ TE 450 and it was a game changer on that bike, but I had to move from a 47 to a 53 tooth sprocket on the rear to keep from stalling on the tight trails; the bike was geared to the moon in stock form.

I assume your asking about a rear MT43? I've never used the tire, but I know of it. Are you riding trials with a KLX50R? I couldn't think of a worse machine to trial ride with. What's your terrain situation, are you thinking of using it for street & dirt use? The MT 43 looks like a larger version of what I used run on my moped when I was 12. I wouldn't want to use it in the mud for sure. And could only imagine what my riding buddies would say when I showed up for a Sunday ride with it. As far as gearing, I've never thought to much about its effect on which tire I'm using in tight conditions. Maybe I should?

I run mine at 4-8psi so the hight does not really make much of a gearing difference

I ride mostly tight single tract stuff, NO Trials!!! (:  yes this is a bit of a portly bike but it is still about 6 lb. littler that what I am coming off of and it carries it weight very well, more like my 250x.  I live in Eastern Idaho so I can ride from my house with a little bit of pavement to connect me with my favorite trail section.  I just got my bike plated and insured; you have to love the good old county girls down at my local DMV that only asked me if my bike had a headlight, taillight and a speedo.  “Why yes mama it does”!

I ran 9 PSI off rode with my Husky and 12 on the pavement these tires are great if you have not tried one give it a chance they are cheap and last a long time.  They do suck in the mud but I try to stay of the trials when it is muddy so the greenies do not close our trials, plus I hate cleaning that crap off.

I run the MT43 on my KLX...12/53 gearing...i run on trails that goats don't dare climb.  My bike is unstoppable.  I run 6-8psi on slow days and 9-10 on fast days.  My KLX is the only trials-capable 450 out there...its an amazing weapon in the right hands.  The sidewall is stiff enough to keep from feeling wobly and squishy on pavement and still soft and pliable enough to grab and grip anything in its path.  My last tire was a Michelin X-11 competition...a better tire IMO but very $$$ for the tubeless model(i still ran uhd tubes) and it felt really squishy and wobly at speed.  300miles on the MT42 and i'll certainly buy another when the time comes...i'm probably gonna put one on my TM250 as well.

I run these Pirelli mt43 front and back, 16psi front,  12 psi rear cold . I have also ran Mich, IRC and Dunlop on other bikes, and my bud Lee swears by Mich. I do like the pirelli' best because they are firmer when loading side wall. This bike and I together are on the heavy side. I would say gearing it down some and useing trials tires are the best mod.