FROM: w.j.markerink@a1.nl (Willem-Jan Markerink)
SUBJECT: Re: tire width and sand
DATE: Wed, 03 Feb 99 19:35:00 GMT
ORGANIZATION: A1 Internet news-server
NEWSGROUPS: rec.autos.4x4

In article <797e66$8t8$1@solaris.cc.vt.edu>,
   John Pollard  wrote:
>
>What tire characteristics are desireable in snow?
>
>My recently acquired '78 Jeep Wagoneer has wide tires and can't make it
>up a snow covered hill that my Subaru climbs with no problems.  I've
>been wondering if I need narrower tires...
>
>John

Wide only helps on bottomless snow, to have you floating on top, but with 
anything else (ie firm ground below), you are better off with a narrow 
tire, especially a siped one, and perhaps even spiked (if allowed in your 
area).
If you still can't make it up that hill, try airing down....although it 
conflicts with the first advice of "narrow is better than wide because it 
cuts through the snow", this often makes the tire bite better in the snow, 
and also clears the thread easier (Icelandic folks sometimes spray their 
clean tires with silicone stuff to get the same effect!).

Some people are convinced that it is the snow-on-snow contact that makes 
a tire grab in the snow, ie a good snow tire should pack up clogged with 
snow, so that snow *in* the tire/thread attaches to the snow on the 
road....but just look at the clear footprint of a snow tire in fresh 
snow....the profile simply stands up almost a centimeter tall....not 
something that would occur with the snow-on-snow concept. Also not 
something the sipes are made for....they are supposed to bite into the 
snow, not get clogged with it.
And at very low temperatures, you would need a lot of tire pressure to 
make the snow attach to itself as well....














FROM: Erik <++kickinit@home.com>
SUBJECT: Re: GMC pickup with AWD!!!!!!
DATE: Sat, 24 Feb 2001 02:11:44 GMT
ORGANIZATION: Excite@Home - The Leader in Broadband http://home.com/faster
NEWSGROUPS: rec.autos.4x4

On Fri, 23 Feb 01 08:40:55 GMT, w.j.markerink@a1.nl (Willem-Jan
Markerink) wrote:

>Aired down tires, fat or not, have proven to get you through on slick 
>snow & ice where ordinary (street) tire pressure couldn't....it's more than 
>just ground pressure, there is also an argument of having as much biting 
>edges on the snow as possible, and being as conformative to the (uneven) 
>ground as possible.
>Btw, note that in the matter of aquaplaning (or better: slush-planing) at 
>medium to higher speeds, things work the opposite way.

Yeah, tread pattern can play a huge role in traction.  I can see how a
decently siped fat tire could help out in ice... all those skinny
biting edges would create many points of maximized static friction
between the tire and the ground.  My previous statements were based on
generalities.

If you have any question, remark, comment, want to share some philosophy or just want to express your opinion about these pages, feel free to send email to: w.j.markerink @ a1.nl