Dunlop GeoMax MX31 front on a YZ450

I live in northern Michigan. I am running the 31 on front and 51 on rear on my yz450. We ride a lot of tight hard packed trails but there are a few open "play" areas made up of soft sand. So far I have been very impressed with the set up. No major signs of wear on the front either. I would definitely recommend them.

I'm running the MX51 on both front and rear. Just wondering what kind of pressures everyone in running on the front. Doesn't seem like the front wants to stick like the 756 does. Just wondering if maybe I'm running a little too high of a pressure (12 psi)

Definitely love the rear. Wear's extremely well. If it weren't for concrete starts it would probably still have a square edge.

Yes I have, and it stunk. The 745 is out of its element in anything softer than true intermediate soils. Pretty good on the harder stuff, but doesn't do well in loose stuff at all.

That's in contrast to my experience where the 745 has been the best tire I have ridden in 16yrs. I have only used the 90/100-21 for the added height for keeping me out of the rock in the Vegas desert and the added sidewall when leaned over. DO you think that has anything to do with our different opinions on the 745?

Also I am anxious to try the MX51 but I'm not sure what size. Dunlop lists the 80/100-21 as having almost the same cross section as the 745 in a 90/100. I am up in the air as to whether or not I should go 80 or 90

I have only used the 90/100-21 ...DO you think that has anything to do with our different opinions on the 745?
I don't think so, since that's the size I used. When I mean soft loose stuff, I mean sand, deep, fine sand and coarse, deep gravel, and silt. It just never held in that stuff like the other tires I mentioned.

However, I'm so much more impressed with the MX51 rear than the MX31, I plan to try one on the front next.

I put on a set of 31s front/rear after coming off of a 755/952 combo and ride the desert only - Ocotillo Wells/Superstion. I am impressed with the sticking power of the 31 in the front for corners and it gave me just a bit more confifdence than the 755. The rear seems to slop around a bit trying to hook up but didn't wash out. I only have 2 hours on the tires and the wear factor seems to be normal. I will try the 51s next.

I don't think so, since that's the size I used. When I mean soft loose stuff, I mean sand, deep, fine sand and coarse, deep gravel, and silt. It just never held in that stuff like the other tires I mentioned.

However, I'm so much more impressed with the MX51 rear than the MX31, I plan to try one on the front next.

Well ok, then we both had the 90/100 so thats a wash. I am definitely going to an MX51 next, but like I said I'm kind of up in the air about 80 or 90. Gray do you think there is a such thing as too wide? What do you think would be the disadvantages of going with the 90/100 which dunlop lists as 3.86 wide, vs the 80/100 which is 3.66 vs the 90/100 in a 745 which is 3.70. Am I making too much out of .16 of an inch? Will it be that significant? The reason I ask is because the 80/100 MX51 looks about the same and the 745.

On the 80 vs. 90 question, I don't know. I've tried a couple of different 90/100x21's and didn't care for them, but to be fair, I have not tried the same tire in both sizes. What I notice, though, is that in general soft terrain front tires tend to be narrower so that they cut down into the surface, and so that they have a bit more room to steer in ruts while hard terrain tires are wider, looking for more surface contact. The trouble I had with both the 745 and the Bridgestone 403 in a 90 was that they skated in sand quite a bit. Most of the 80's work better for me.

I ran the 31 up front with the 51 out back and just changed out the front (which stuck in the corners extremely well!) for the 51 due to the fact that the outermost row of knobs were tearing off (all of them, all the way around) after only a few hours on a sand/clay mix moist to hard packed with very few rocks.

The 51 is very grippy also in the same conditions. Not quite as much as the 31 however but still very good and gives me a lot of confidence. I will have to wait and see about the outer row coming off but after 1 hour there are no hints of tearing yet.

I run 12 psi F/R.

I'm thinking about getting the knobby knife to keep the back sharp as it starts to round which it is doing slightly now after 4-5 hours. Has anybody used it? what do you think?

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