[Farmall] M - Tricycle Wheel Spacing

[Howard R Pletcher]

After the last "food fight" on the subject, my analysis of the situation
is that with a tricycle front, you have the CG of the tractor pivoting
around a point on the ground and this CG is probably 36-48" or more above
the ground (depending upon what tractor we are looking at) and much
higher with that bucket full of rocks raised overhead.  Once the CG moves
enough sideways to be outside a line from one rear wheel to the fronts
(the triangular stability area), it's going over.

With a wide front that same CG is trying to pivot around a line from the
ground under the rear wheels up to the pivot point of the front axle.  If
the CG is about in the center of the fractor, fore and aft, the distance
the weight is trying to rotate about will be reduced by 1/2 the height of
the axle pivot.  If the pivot is 24" above the gound, the lever arm is
reduced by 12", which relative to a 48" CG height, has a measurable
effect, but doesn't make it into an off-road vehicle.

But the stability area Roberto mentions is not a recangular area with a
wide front UNTIL the tractor tips to the point that it hits the axle
stop. Until then, it just pivots about the pivot pin allmost like a
tricycle.  At this point, I think you'd already be past the point of no
return.

As a practical matter, I would say that whatever angle the tricycle rolls
at would still be outside my comfort zone if I were operating a wide
front, or as Mike says, it's a small percentage difference.

Howard

On Fri, 22 Apr 2005 11:22:10 -0400 Mike Sloane <mikesloane at verizon.net>
writes:
> Not to start up an old food fight, but I have had dealings with several

> rolled over tractors with loaders (fortunately none involving me on 
> them!), all wide front, and I never have seen a similar narrow front 
> rolled. (Maybe folks with narrow front tractors are more careful?) If 
> there is a difference in stability, it is, to my mind, a very small 
> percentage. 


On Fri, 22 Apr 2005 14:40:31 -0400 Roberto Rivero <rj.rivero at gmail.com>
writes:
>the physics laws involved here are about stability, and  that 
> means the center of gravity stays as low as possible and inside the 
> stability area, which yes in a WFE is a rectangular area and in a  NFE
is a 
> triangular area, but i see very difficult that the center of gravity
falls 
> outside the triangle of the NFE