Tires Loaded Front Tires Resist Tipping?

[Henro]

Hi,

A while back there was a thread related to loaded tires and tractor stability on slopes. It is accepted that loading the rear tires will make a tractor more stable on a slope, especially a side slope.

Someone in the tread I am thinking of posted that since the front axle is on a pivot point, that the tractor would tip the same whether the tires on the front were loaded or simply air filled.

At first thought this seemed reasonable. So I wrote off the added weight of my foam-filled front tires as being of no worth, as far as side-slope stability and roll over prevention goes.

This morning I turned my brain on and now think that the extra weight of my front tires does in fact add to my tractor’s side-slope stability and would help fight against a side-slope caused roll over.

This is because the front axle and tires hang from the center pivot point, and if the tractor started to tip, it would have to lift that weight off the ground, just like the rear axle is lifted. This weight may, or may not, come into play before the end stop on the front axle is reached. But it would have an effect.

So my conclusion is that the weight of the front axle, and the tires attached to it, do indeed affect tractor stability.

Is my thinking flawed?

 

[BigAl]

Hi Henro ,
I don't know if your thinking is flawed or not, but awhile ago there was a Aussie fellow who posted a thread about this . He swore by loaded front tires . I never gave it much thought ,as I usally only had the rears loaded on my tractors in the past . On my new tractor I had the front and rears loaded . I really have not had much chance to evaluate front loaded tires ,since this was done . That will come this summer on the old ranch.
Big Al

 

[Poppa]

Henro, I think loaded tires would have to help. Anything put BELOW the center of gravity is going to help lower that CG and make the tractor more stable. Does it help a lot? Well, that is math and I don't like math but it sure can't be hurting.

Mike

 

[rockyridgefarm]

Good news, Henro!

The TBN/PSU tractor rollover research project is going to answer this very question. We will be performing tests THIS WEEKEND. And the good news gets even better, because the test are to be done on equipment very similar to yours and terrain very similar to yours. And very near you, no less.

Wait, it IS your equipment, at YOUR House...

What's for lunch?!!!!

/forums/images/graemlins/grin.gif

btw, i am in agreement on the cg side, but i also think there are possible situations where loaded tires COULD add to instability, like on a pond dam.

 

[RonR]

Henro, do you have any other hobbies, besides making everyone here engage their brains a lot?????? /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif

Why my daughter was 2ish, she asked so many "WHY" questions, I had her trained when she met someone new to say "Hi, my name is Cindy, and I'm in the WHY stage." It was cute for everyone!

Best wishes, and keep the hard questions coming. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[BB_TX]

Henro-I agree with you to some extent. I don't think the extra weight would have any effect at all until the tire actually started to lift. Up to that point, it is not providing any down weight to the tractor frame since the axle is pivoting. The tractor is still providing down force on the wheel rather than vice/versa. At the point the wheel starts to raise, then real weight is transferred to the frame itself. Whether that would be enough to stop the rotational motion of the tractor would be different for all situations and essentially indeterminate. /forums/images/graemlins/crazy.gif

 

[Poppa]

BB's right on. The added weight of the tire would not become a factor until the rolling motion of the tractor began to lift that wheel off the ground. Therefore anything other than a straight back flip would be adding the weight of only one of the filled tires to the tractor. So, it seems to me that the question is, if the minor (relative to the tractor as a whole)amount of added weight from the ballast in the smaller front tire would have enough effect to stop and reverse the rolling motion of the tractor.

Hope not to find out /forums/images/graemlins/grin.gif

Mike

 

[Bob_Skurka]

BB . . . I generally agree with your points, but would think that the effect of the loaded tires (front or rear) would differ depending on the slope the tractor is traversing.

Taking my theory to the extreem I believe we should put Henro's tractor on a 45-degree slope and see if the the center of gravity is above or below the loaded tires that are on the high side of the slope. It is very possible that, depending on the steepness of the slope, the C-O-G could be below the loaded tires that are on the high side of the slope and the loaded tires could actually increase the chance of a rollover.

 

[JASTN70D]

I believe that the more weight the tractor would have to lift below COG in order to side roll the more force it would take to roll I. E. More stable. How much more stable is the question not if.

 

[JerryG]

How is it going to help stability UNTIL the axle hits the stops?