Thread: Are huge tyres worth it?

Originally Posted by TJWA

I've since been told that a leading Australian 4wd magazine has published that it is the length of the tyres, not the width, that makes the difference on sand when let down.

To clarify, the test demonstrated that as you deflate the tyre, the footprint becomes longer, not wider as some people seem to think. The test was about footprint shape, not sand performance.

On the other hand, there was another article done by Roothy on Milo when he changed from skinnies to fats, and he preferred the fats.

The other misconception is that a tall skinny tyre will provide more floatation than a wide tyre which is also incorrect. a 7.50R16 (31") skinny will lengthen when deflated to the same length foot print as a 31x10.5 for example with pressure adjusted to suit the carcass. The fat however has greater width so the larger footprint provides greater floatation.

With regards to mud traction, a skinny will sink quickly, but a fat mud tyre will also clear the mud if it is spun and it will bite down. You will notice that all comp mud tyres, all comp sand tyres etc are very wide tyres - there are very few skinnies out there. Comp tyres are designed with a purpose in mind and to do that well - so they are wide. Likewise many people say that sand tyres should be closed pattern highway tyres, but all comp sand tyres are open pattern and paddle design.

In 1976 me and two mates all bought Nissan Patrols (we were young). I remember we couldnt get a discount for 3.
They were identical & all performed identically as we tried to "outrun each other" often & there was painfully little in it between them all through the gears- on bitumen.
They came with "roadtrack majors" from memory & one of my mates soon bought some wide 15" tyres but with the same OD - 31".
Guess what - he kept dropping behind on straight accelleration, hills etc.
So we swapped the tyres around- yep, lack of performance on whatever Nissan they were fitted. To make matters worse, they were'nt noticeably better 4w'ding, in fact we would get ahead there too. We put this all down to rolling resistance.
As an aside I took my series 2 LWB along on a snow trip - I was trying to sell it priveatly and it beat the other two hands down in the snow, actually this upset me as I had dropped $4,500 on a new 4wd that the $800 Landie at the time would go better in the bush. Around the campfire we determined it was simply the bar treads Vs all terrains. We could'nt swap the wheels around as the Nissan was 6 stud ( which were useless- they broke).
Regards, David