(This will be my 3rd winter on my 106's.) It's the trafficked snow that my 106's have trouble with. They just aren't wide enough, with enough of an aggressive tread (esp near the sides) to deal with all the ruts that car tire tracks going every-which-way leave. I have found out that lowering my tire pressure down to almost 25psi helps, but making it around messy corners with lots of slop (which most corners have in the winter where i live) is a real squirrely endevour. Also, shift as much of you body weigh as you can back and onto the saddle. Keep your arm pressure very light.