R4 vs. Turf Tires

[BRENTK]

I will be purchasing a JD 4300 in the next week or two. I am undeceided on which tire to get. I would like the R4 for loader work and snow removal, but I am concerned it will rip up the lawn while mowing. For those of you with tractors of this size and R4's, has turf damage been a problem?

Thanks in advance for your advice.

 

[Chris in IN]

Brent I drive my 4400 with R4's on turff all the time. Only when the ground is wet after a rain is there a problem. I do not have a finish mower, but do alot of work with the loader & tiller. I am very happy with the R4's. Chris

 

[James]

I have R4 tires, and the only time that I get a rut is if the ground is wet, or very damp. They work great with the front end loader. I am very happy with mine also. I use my tractor mainly to mow my yard, and don't think I would have been happy with the turfs after having the R4's.

 

[MChalkley]

I think turf tires are very special-purpose tires and really truly useful only for turf applications. R4's are much more versatile and durable. You can use them for turf applications with a little care, but if you do much loader work, I think you'd regret getting turf tires.

Mark

 

[TomG]

I've been boosting turfs for awhile, saying that I didn't have traction problems. That changed. I wanted to take off a turf over-burden to prepare a pad for a construction trailer. Had to take small bites with the scraifiers down one notch on a 6' box blade until I got the turf off. The traction was OK on dirt.

I don't use the tractor for mowing, so it will be R4's for me. However, I'll probably wait until the loader finishes off the front tires, or I pick up enough nails from our demolition that I can use the rear tires for colanders.

 

[gerard]

R4's. I went with the Ags and am happy with the traction but to do it over again I'd defintitely go with the R4's. AS Mark said, more versatile and won't impress the ground too much unless REALLY soft. I think the R4's also have more plies and are more puncture resistant.

 

[MChalkley]

Yes, the R4's are definitely more puncture resistant, durable and weight capacity. My first Kubota had turf tires because I didn't know any better. I had them two weeks, during which time I had 4 or 5 flats to locust thorns. After pushing a stick through one of the front tires' sidewall and ruining it, I made the switch to R4's and have never looked back.

Mark

 

[JBM]

It may make a difference on the type of soil you have. My nine year old B1550 has R4's and my newer B2400 has turf tires. I found that here in Florida where the soil is really just sand, the R4's can tear up a lawn - especially when it is as dry as it has been.
JB

 

[MChalkley]

I can see that happening - I lived in West Palm Beach for 3 years. I guess down there you'd just about need two machines if you needed a loader and wanted to mow grass, too.

Mark

 

[GaryK]

I tried both before I bought and went with the r4s, have mowed the lawn a few times and no damage, you just have to be careful on a wet lawn and no sharp turns at fast speeds. R4s didn't leave any impressions on lawn either.

 

[MChalkley]

Something I learned a while back from an engineer who specializes in such things is that the ground pressure exerted by a tire is largely dependent on the air pressure in the tire. So, if they're over-inflated, as is usually the case, the damage will be much more severe.

Mark

 

[W5FL]

Interesting observation. Obviously the weight of the tractor at each tire divided by the sq inches on the ground is the pressure on the ground in psi. To a large extent this is dependent on the pressure in the tire. I believe mine show 18 psi rear and 34 psi front with a tractor weight of 8000#.

From Firestones Web Page: The footprint at no penetration/3 in penetration:

16.9x30 R1 Ag Tread 3750#@18psi 216 sq in/540 sq in
9.5x24 R1 Ag Tread 1870@30psi 79 sq in/245 sq in

Assume reasonably equal loading with loader and all wheels filled with ballast. The loading would be about 1/2 of this without a loader and without ballast.

13.55 psi loading on the grass with no penetration
5.0955 psi loading on the dirt with 3 in penetration

That seems like very little ground loading with an 8000# tractor. It would be interesting to see what it would be at lower inflation pressure but I could not find that data.

I imagine that turfs will come in about the lower value of 5 psi and R4 tread will be somewhere between 5 and 13 psi. Wonder if this loading is pretty constant with different size Kubotas?

Tell JimBinMI that I used EXCEL to do the calculations, but he needs to come over and check them. /w3tcompact/icons/smile.gif

 

[Anonymous Poster]

The average contact pressure on the soil at the tire footprint is always about 1-2 psi more than the inflation pressure in any tire be it radial, bias, R-2, R-4, etc. If the tire were simply a tube (a membrane) the average contact pressure would be the same as the inflation pressure. However, since the tire carcus has some stiffness, the average contact pressure is 1-2 psi higher than the inflation pressure. It is important to use the term "average" because it is not uniform pressure. Under the lugs it is higher and between lugs it is much lower. However, when averaged over the entire footprint area the contact pressure is just a little bit higher than inflation pressure. When comparing two different tires on the same tractor, the important consideration is the inflation pressure required in each tire to support the same axle load. Small volume tires require more inflation pressure than larger volume tires. Comparision of footprint areas from a handbook is not very reliable because the published area is always that area that occurs when the tire is carrying its maximum rated load and inflated to the maximum required pressure. Very few tractor tires operate there. Normally the load and the corresponding pressure would be much lower.

 

[JimBinMI]

Wen,

I won't check you, got better things to do. I'm working on being kinder and gentler with you Orange boys!

And just for the record and you can quote me, IF I could have bought more Kubota for equal or less money I probably would be an Orange owner right now! As is was/is I bought more tractor for less money with similar quality, assembled in the good ole USA and I have a great dealer! Even Steve Carver couldn't believe the prices at my area Kubota dealer!

JimBinMI

We boys and our toys!

 

[W5FL]

Now that is a paradox. A kinder and gentler french blue you. /w3tcompact/icons/smile.gif

Steve couldn't believe the prices were that low or that high at your Kubota Dealer?

What were you doing at a Kubota dealer? Are you secretly negociating to trade up to a Kubota with enough HP to run a tiller????