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Trials Tire Test

By Eric Kangas

I have spent a many hours and miles running the Michelin X-11 Competition rear trials tire on my '01 GasGas 300XC. I wanted to share what I have found.

First of all, I am an intermediate level rider who does mostly trail riding. I do not compete. I weigh about 250 lbs gear on ready to ride. Most of my riding is on trails in wooded areas in Western Washington and Oregon. Most of the soil is hard clay, with a lot of rocks and tree roots. Most of the year the clay is wet. When it is wet, the clay is very greasy. Next to ice, wet rocky and rooted infested clay is the most difficult trail condition to ride on.

As an Engineer I like to look at things objectively. To make sure that I objectively evaluate rear off-road tires for trail riding, I run them on a couple of nearby *test* hills in the woods of Western Washington. In the fall, winter and spring these hills are wet slimy clay and rocks, making them very challenging to climb. I have used the Dunlop 739, Dunlop 739 AT, Dunlop 756, Michelin S-12, Michelin H-12, Bridgestone ED78, IRC ix05h. I have had the best knobby tire performance with the Dunlop 756, Michelin S-12 and Michelin H-12. The hills are steep enough and technical enough that I can just make over the top of the hills with a good knobby as long as I maintain momentum and a good line.

On those same slimy wet clay and rock test hills with the Michelin X-11 rear Trials tire, I could accelerate up the hills and in some areas even lift the front wheel. The grip was so much better, I was astonished. Further, I have climbed some even steeper wet clay hills with the Michelin trials tire that I could not climb with any knobby tire. To this day, I am still impressed at where I can go with the Michelin trials tire. The Michelin trials tire works very well in loam. It is excellent on fireroads. It works quite well in sandy trails. It works well in snow up to about 4 inches deep and on snow covered rocks. It is outstanding in pure rocks. It even works well in the deep mud bogs if you torque it along, rather that massive spinning like a knobby. I even ran it a few times on a track. It worked fine there as well. I have run it at speed on tracks, fireroads and in the sand. It is stable, smooth and handles very predictably at any speed. It is DOT rated so you can even run it on the highway on a dualsport.

I installed my first Michelin X-11 trials tire early spring ’01. I put 820 miles on my first one. It started to lose its effectiveness at about 700 miles. It has worn down about 40%, but not a single knob has ripped off or chunked, even with full throttle on rocks and gravel/rock logging roads. There are cracks at the base of the knobs where the knob meets the tire, but they are all intact. As a reference, I would normally get about 300 miles on a Dunlop 756 before knobs were so well rounded, worn down and missing/chunked out that I changed it.

The key to riding with a trials tire in slimy mud is NOT to spin. Get it to grip by starting real easy, torquing along a gear high and steadily roll on the throttle without minimal spinning. The bike will move forward surprisingly well. If you just nail the throttle it will wildly spin just like anything else. A trials tire grips, where a knobby digs and throws dirt/mud. In the dryer conditions you can use full throttle and be rewarded by outstanding hookup and easy wheelies.

Compared to a knobby the Michelin trials tire is:

> Much, much better traction in just about every trail condition.

> Much easier to maintain a line, up or downhill

> Much better rut crossing and staying out of ruts.

> Much easier to start out while on a hill.

> Much better rear braking and improved rear braking control especially on downhills.

> Much smoother rear tire ride, especially on rocks. The tire adds more shock absorption resulting in less bouncing and chattering.

> Feels squishier and flexes more on cornering. However, it is very predictable and stays hooked up very well. In the really slimy conditions it positively blows away a knobby in the corners. You can very easily and predictably brake slide the rear tire in corners if you desire.

> Clears mud much better. The tire easily clears sticky clay mud at speeds above 10 to 15 mph as long as you are going forward and not just wildly spinning the tire. It clears mud much better than a Dunlop 756 or Michelin H-12 on the front!!. The trials tire will be clear of mud while the front tire is packed half full of mud.

> More sensitive to tire pressure. I have found about 8 psi works best all around. Even a few psi higher will noticeably reduce its effectiveness. For very muddy conditions you may want to go a little lower, like 7 psi.

> Offer outstanding rim protection. I regularly smash through rocks and roots mile after mile. The front rim with a 756 at 15 psi comes back with black rubber marks all over the edge of the rim from the severe impact of the tire on the rim. The rear rim has not a single rubber mark at all when running at 8 psi. It is amazing. I run a heavy duty tube. So far no flats, in spite of all rocks I have hit.

A few additional notes: The Michelin X-11 is DOT approved. TT designates Tube type TL designates Tubeless. Either will work, as you will need to use a tube anyway, unless you have a trials rim for tubeless tires.

1) A trials tire will require some change to your riding style, as it gets its traction from gripping as opposed to the digging and throwing done by a knobby. Try not to spin as much and it will reward you very nicely.
2) On hills be careful as you may find your front end wheeling up much easier and looping out more easliy.
3) Tighten down the rimlock(s) very, very securely or it will slip on the rim due to the exceptional grip and low pressure.
4) Cracks will likely appear at the back side base of the knobs, due to braking. Cracks will also likely appear first at the front side base of the knobs, due to acceleration. Do not panic, the knobs are quite secure for offroad high power application. I have never had a knob rip off.
5) The tire does not work well on steeper hills in deep loose dry material like sand or cinder.

For me the trials tire is the only way to go.

Eric in WA
’01 GasGas 300XC

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