Why narrow front tractors

Any volunteers to drive. LOL

Just thought of another reason for the wide front popularity. If you have ever driven a narrow through much mud it becomes real obvious the advantage a WF has.

As I stated earlier. IHC really stablized the NF configuration we know when they brought out the Regular. Only reason that one had the NF was for the mounting of cultivators and later corn pickers.

Once again hope this isn't too much gas on the fire.

jt

Anyway, a couple of things come to mind:

1-The people who are quick to say that NF's are less stable "obviously" have little or no experience with them.

2-It's an operator issue, folks! Use common sense; if what you are doing doesn't feel right don't do it, and go slowly in questionable spots.

We used a NF Farmall M and a NF M-H 44 for years on our hills and never a problem. Also used it with a loader too with no problems.

All of the tests and formulas in the world can't replace safe operating practices.

Now I'm wondering why I jumped in on this topic again; thought I'd sworn off toalking about this issue.

I learned at a young age that going down hill isn't very safe either. I was on a riding mower with bar tread tires. Well I soon learned that when you go down hill with bar treads they try to hold back,but then they are turning backwards which doesn't let them grab the ground. So I was actually gaining speed with the rear tires sliding along.Lucky nothing but flat yard area at bottom.

Guess I will weigh in on this one. Dave is partially right. Most narrow fronts are not a Tripod but a tradizoid that is what makes them more stable. Actually all wide fronts are a tripod (excluding the new active suspensions).

As mentioned earlier in the thread row crop farming was the ONLY reason the narrow front came into being. IE mounted cultivators and pickers.

Hope I didn't put to much gas on the fire LOL

jt

On the tripod, I think it is what it is because it is the only geometric configuration that you can stabilize easily even when the legs are not exactly equal in length and the mounting surface (floor, dirt or what have you) is not perfectly flat.

2 point will fall over.

4 or more and one leg will always carry a disproportionate part of the load if carrying any load at all.

That's what I read anyway, makes sense and I believe it.

On wide fronts, my feelings are that since the thing has one pivot point in the front of the tractor you essentially have a tripod just like the tricycle.

Difference is (my opinion) if you fall in a hole or other disturbance with one wheel, you have essentially affected half the front of the tractor not the whole thing.....but that's not to say that you couldn't still roll.

And, in turning, the force vector, like the top of your body swinging out in a turn like a car going around a curve at 60 mph, can point to the inside of "the box" with a tire out beyond you (if you aren't turning too fast) while on the tricycle, any turn and that vector is outside the tire.....hence the inherent instability.....unless you use the foot brake to turn then all bets are off.

Mark

It takes only bumpy ground at modest speeds on a moderate side hill to roll any tractor. A narrow front tractor may have had the rear wheels set narrow for rowcrop use. The wide front tractor may have a wider stance and be more stable. Because the wheels are set right out flush to the ends of the axle from the factory. Not too many people go through the work of regularly changing rear tread widths. Around here the collectable narrow fronts are all set with the rear wheels out flush to the axle ends. At some shows I've seen narrow front row crops with the rear wheels set as narrow as possible. The sides of the tires are "almost rubbing the operator's foot rests". They look like a couple of kids could tip them over with a good push.

Anyhew I figured they did it to get it on the trailer to move it from where they got it to where they fixed it, to where I bought it.

As soon as I got home I moved them out to bout 8'. Learned how to move JD wheels.

Just standing behind the thing you could see that it was unstable.

On the difference of the two, just go back to the force vector....pendilum weight swinging out kinda thing, or just watch your outside tire on a wide front when you turn a corner.

You can see the forces acting on the front end and see that the outside tire is taking the load....and on a tricycle, that tire isn't out there regardless of the fact that they both pivot in the center.....something just hit me.

The length of the front brace (of the triangle) on a tricycle goes all the way to the ground. On a wide front, it only goes to the top of the front axle; half the distance.

So that arm is half as long so the pendilum swing would only be half (almost) as far out for the same pressure. Wides are more stable inherently...just convinced myself of that.

Mark

Buys tractor.....Farmall B tricycle.

Hook up plow.

Plows to end of row.

Lifts plow while.....

Hits appropriate brake (left for left turn), turns loose of the steering wheel.

Tractor does about face in it"s own tire print.

Drops plow at end of turn.

Starts reverse row.

No time or distance lost per se.

Question answered.

The very first tractors (steam powered, then Waterloo Boy and such) were wide front because they were modeled on a wagon and people used them in place of a horse team to drag things around.

The narrow front tractor was created to allow the use of a front-mount cultivator and a mounted corn picker. They were also possibly cheaper, turned shorter, and were definitely simpler and easier to maintain.

Those of us who grew up on the tricycle tractors had to know how to operate them safely. Loader down, rear wheels out, limited side slope, watch for bumps and rocks, and go SLOW.

This issue sure gets people goin' don't it? :>)

That reminds me, gotta take that blood pressure medicene. :>)

Allan

Ask your doctor about Coenzyme CQ10 or go to Dr. Stephen Sinatra MD's website "drsinatra.com". He's a renound cardiologist with a clinic and MD training center in New England among other things. Might prove interesting brousing.

He's different. If you need the knife he says go for it..... but he has other "alternatives" that he tries when he thinks they are appropriate. Does a lot of explaning about what is really going on with cordiovascular things... including all (a lot of) the operations that aren't necessary or could be easily avoided. I like that. Best of both worlds.

Best,

Mark

You probably just opened a can of worms that you won't believe.

But you be right. :>)

Allan

I can see why you are confused, and I can understand why your gut is telling you different. The truth of the matter is that it is not that a narrow front is a model for stability. It is just that people get a false sense of security with a wide front. Because of the way the front axle pivots on a wide front, your pivot point is effectively much the same as a narrow front. So even there are "stops" on the wide front, by the time you hit the "stops", the tractor is already on it's way over. The only absolute way to avoid a rollover is to avoid side hills, and avoid raising the center of gravity on the tractor while on any side hill (raised loader with a load, etc).

Hope this isn't too confusing, but the main thing to remember is that all tractors are quite suceptible to roll over, no matter what their configuration, due to relatively high center of gravity.

On a hill, the closer the pivot is to the ground, the greater the roll moment is. If the pivot was at the centre of mass, you would have roll or slip based on the tires geometry.

When the tractor is on the incline the vector at the center of mass (CM) moves downhill whereas, the NF vector doesn't. The front wheel vector becomes 'uphill' with respect to the CM vector and thus providing no resistance to a rollover. However, with a WF the downhill front wheel remains 'downhill' with respect to the CM vector and therefore continues to provide resistance to a rollover.

When the CM vector moment exceeds the sum of the vector moments from the downhill wheels the roll over is completed.

The narrow front *will* roll first. In a simple static test there is no other outcome possible.

In bouncing fields and varied wheel spacings and different operators anything is possible.

We could draw up a little model and do some calcs for fun but we would see with the rear tires set narrow enough, the wide front is always more stable.

With the rear tires set as wide as possible, there will come a point where the difference in stability is negligable.

As part of this too, some wide fronts are only minimally more stable. Look at some of the IH's with a very low axle pivot relative to the engine height. In these cases you will find very little difference in stability.

Utility tractors are nowadays designed with a very high pivot for stability. This actually decrease the ride comfort a bit as bumps will push the tractor slightly sideways but on sidehills the stability is increased.