Loaded Tire experts...Help!!

[BeeBop]

I am noticeing an unfavorable premature wearing around the center of my R-4 tires. They are loaded from the dealer and have about 18 lbs to 15 lbs in the tires as I last recall. The tires don't look as they are getting total footprint on the ground, almost has the appearance of an over inflated tire? Is it possible that too much loading was done and if so how would one verify this problem? Thanks..

 

[beenthere]

Loaded? as in 'filled with fluid'? or wheel weights? or back-hoe?
Sounds like you know the answer, that the tires are over inflated.
But, what does your manual say for tire pressure on the R-4's?

I would let some air out so the foot print looks right.

 

[dgood1]

I concur. Sounds over inflated.

Just my opinion though,

Don

 

[Mrwurm]

I have heard of people using the following procedure:

Find out the acceptable psi range for your tires.

Fill them to the max inflation rating.

Let air out until the outer lugs on your tires are touching the ground (best done on pavement) But don't go below the minimum rated psi.

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Hope this helps.

 

[joecdeere]

Too much air for sure, we used to wet the grass with a hose, drive through it and onto the drive to check our foot print, R-4's are hard to judge on

 

[John_Mc]

Loaded tires should be filled a max of "75%" (actually they are usually filled just enough to cover the top side of the rim, especially when using corrosive liquids such as Calcium Chloride.) You definitely want some air left to act as a "shock absorber" and allow the tire to deflect a bit when it hits a bump. Otherwise it's a very jarring ride for you and for the tractor.

It does sound as though your pressure is too high. You generally run a bit lower air pressure with loaded tires than you would with just air. As others recommended, I'd let out enough to leave yourself a nice footprint when carrying whatever is a typical load for you.

It's possible there is too much liquid in your tires, but I'd try letting the air out first. Stop with the tire stems at the top of the rotation and let out some air. If liquid comes out, they may well be overfilled. If you have CaCl or other corrosive fill, it's best to be sure to rinse off the tractor wherever the fill may have dribbled.

John Mc

 

[BeeBop]

Thanks for the replys guys. I will let some air out as I will check the liquid as well. If this does turn out to be too much liquid how would one go about removing it and setting it to the right amount?

 

[chim]

First of all, I'm no expert. I can tell you some things from personal experience though. My 12-16.5 R4 rear tires each have 15 gallons of antifreeze/water mix. This is less than it takes to cover the wheel, but since corrosion is not an issue with that liquid that's OK. It does allow me to add or bleed air without adding or removing liquid.

Just last night I aired down to 7# from the 10# I had been running, and it made a noticeable difference in the ride comfort. I do not understand the physics of having a tire 25 or 50 or 75% liquid-filled as it relates to the level of air pressure required for proper operation. (I do know that anything near 100% liquid fill is a big "no-no".)

If you check the string "Pop Goes The Kubota!!" under Kubota Buying/Pricing there is more info and pics............chim

 

[dgood1]

Chim,

The more water, the more weight. Therefore 75% = most weight.

Water doesn't compress or if it does it won't very much. That's why you need to keep water out of injector pumps.

If you have 25% air then when you hit a bump the air can compress and ablsorb the shock. Water won't and will cause something else to give. Like maybe the tire sidewall.

This is as I understand the world,

Don

 

[BeeBop]

You guys were so right, too much air. I couldn't accept in my mind that 16lbs or so was too much but it was. I aired them down to 9 or 10lbs and now it has a Bigfoot on the ground, great contact. Thanks all!

 

[chim]

Don, thanks. That is the way I understand it. What I'm lost with is not having a formula or cheat sheet to determine how much pressure is optimum for best tire performance with different percentages of fill. It seems like the relationship is non-linear. I've been to tire manufacturer websites prior to filling my tires to see fill recommendations, but don't remember seeing inflation values. Maybe with all the tire sizes and tractor weights to deal with it would be tough for manufacturers to cover pressures.....................chim

 

[dgood1]

Chim,

I'm not sure that there is much of a relationship. The only thing that I think that you need to do is go by what the mfg recommends for the unfilled tire and adjust for personal preferences.

I think that you only need to have enough air to keep the tire bead seated on the rim. You don't want your tire to stay still while the rim spins inside the tire.

Just my opinion,

Don

 

[John_Mc]

<font color=blue>I think that you only need to have enough air to keep the tire bead seated on the rim.</font color=blue>

You probably also want to avoid excessive sidewall flexing, since this could affect the life of your tire, and will make handling a bit mushy.

 

[Kodiak]

I would like to add the safety aspect also. Lowering your air pressure can have great advantages as to traction and ride comfort. However there can be some adverse efffects by lowering it to much. As in to much sidewall flex during a sharp turn or on a sidehill. If your tire is to soft the high center of gravity versus the soft sidewall might result in the tire rolling back under the rim on the downhill side or outside of a turn and this could cause an unexpected rollover. Remember that for every tractor out there there is a different combo of operator, tractor,options and load weight at at a different heights, effecting the center of gravity differently. Its just a matter of common sense, not an absolute value set in stone. So please be safe.