GUIDELINES FOR SNOWMOBILE TRAIL
           GROOMER OPERATOR TRAINING


A Resource Guide for Trail Grooming Managers and Equipment Operators:


Chapter 1 - Introduction To Trail Grooming
      .
Trail Grooming Principles:
 
It is important that the basic principles of snowmobile trail grooming are understood in order to properly operate trail grooming equipment and achieve the desired result of smooth, firm trails.

Working a heavily moguled trail back into a smooth surface, that will last, is probably the most difficult aspect of trail grooming. To accomplish this successfully, it is important to understand the characteristics of moguls.

Mogul Formation The primary reason snowmobile trail grooming is necessary is the continuous formation
of moguls by passing snowmobile traffic. Moguls are patterns of mounds and dips formed in the trail’s snow surface perpendicular to the direction of snowmobile travel.

Moguls in snowmobile trails are caused by passing snowmobiles just as “washboards” are created in gravel roads by passing vehicles. Gravel roads have to regularly be graded. Similarly, snowmobile trails must be regularly groomed. Moguls are as undesirable to snowmobilers as washboards are to motorists.

      

Figure 1.1 demonstrates how moguls are formed. In the top view, a small rut is created in the trail by a snowmobile that has either braked suddenly or accelerated too quickly. Views 2, 3, and 4 show how the rut develops into a run of moguls as the suspensions of many successive snowmobiles react to the uneven trail surface, each one compounding
the other, as each snowmobile passes.

Today’s modern snowmobile, with its carbide runners that cut the snow surface and up to two-inch deep track lugs that dig out the snow, is an unintentionally effective digging machine.

As a result, snowmobile riders innocently destroy the surface they desire to be smooth. Moguls tend to form wherever snowmobiles accelerate quickly or slow down abruptly.

This can include before and after curves, approaching and leaving stop signs, before and after bridges, or on steep hills. These areas all require extra attention by the groomer operator.

   

Photo 1.2 Curves and areas where snowmobiles cut onto trails require special attention.

Moguls also tend to form in long, coherent stretches or runs on relatively flat, open sections of trail. Each passing snowmobile, as the suspension extends and contracts, causes the mounds to get higher and the dips to get deeper the same distance apart from one another in a constant, unchanging rhythm that pounds both machine and rider and makes the ride most unpleasant.

And the greater the speed, the more suspensions will expand and contract. In these locations, it can be important that a drag, with its length and planer effect, is used to level the trail versus trying to “groom” with the front tractor blade, which can often further accentuate the rhythm of this type of moguling.

               

Moguls can also be caused by “natural formation” in situations Photo 1.3, A snowmobile’s skis, track, and suspension all where there is warm contribute to mogul formation ground or creeks under the snow, as well as by the alternating effects of sun and shade.

 



  Next Section -  The Four Steps of Trail Grooming

Support Us By Supporting Our Sponsors.
Please Let Our Sponsors Know You Found Them On AbsoluteSnowmobile