Why does no manufacturer offer to mix tire types?

[majorwager]

Jeffy,

At the speeds typically traveled by compact tractors, and in consideration of the softer surfaces upon which they are driven, fuel savings are negligible. Prolonged logevtivity is also in dispute. By your own words, compacts accumulate only about 80-100 operating hours annually.

As an example of longevity, I own a 1993 compact w 2000 hrs. Tires never abused, or spun excessivly. Tread depth is within several thirty seconds of the original. Stored inside, so minimal dry checking, or UV degradation. So just how long do you believe these R-3 tires should last?

Michelin reports the tractive effort increase over bias ply is 20 percent +/-. Not sure if that stat is relative to light nature of compacts, 2-1/2 tons and less. Was noted that most construction machines are much heavier, to benefit the radial advantage.

Radials are more expensive and not all sizes are available but selection is improving.

If you truly feel that radials are such a substantial advantage, why have YOU NOT equipped your own tractor w/ this feature?

EDIT::

Bias compact tires are operated at 15 to 18 psi. You allege a softer ride w/ radials on a compact? Ridiculous. You state directly that radials would operate at lower PSI than bias ply. From where is this information obtained, as it is inaccurate. What is the PSI recommendation for TP in your kubota OM? The footprint slightly wider, alas 20 percent more traction.

As for compaction factor using a CUT tractor, radial or bias, is twilight zone science. Where do you source this nonsense?

 

[4570Man]

I’ve never seen radials offered on small tractors, but maybe I’ve missed something. And the cost to change tires after the fact is substantial. It’s not a lot of difference at the start.

 

[Turbys_1700]

I would assume that manufacturers would offer and R1/AG1 combo if there was market demand for it and could match the rolling circumferences...
Much easier to stick with an R1 or R4 standard from a cost standpoint...
Radials are more common in AG applications and on larger tractors...
My T4.75 came with them and I like them so far...
I prefer tubeless over tubes so that I can plug and go...
R4's...
Meh...
Prefer Ag's for my applications...
I've run both...
Personal preference...

 

[jeff9366]

I know that it's not as simple as slapping on whatever you feel like, but getting the ratios right couldn't be that hard.

I just blundered on this tire lead/lag calculator:

Lead Lag Calculator




Michelin Radial Tractor Tires: Reducing compaction / Properly use your tires - Michelin Agricultural Tires

 

[rScotty]

I've been researching / agonizing over tires recently. I'd like to give turfs a try, and the tractor now has R4's. To do that, I need new rims. The price is around $1,500 for new rims and tires. Some money could be recouped by selling the rims and decent rears. The existing rear tires have lots of tread and the fronts are showing pretty much wear.

One thing I've been thinking about was to just change the fronts from R4 to turf. The R4's have always done a good job. I have noticed that brand new (front) R4's can tend to mark grass when making sharper turns. There's a lot of info about rolling diameter of tires that needs to be considered. Just how much the rolling diameter of the tires has changed with the wear they now have isn't something I know.

I have found turfs that are very close to the R4 rolling diameters and have done the calculations comparing them. The one piece of information I haven't found so far is the front-to-rear gear ratio of the tractor to see what the original tire ratio was. From what I've read, the final ratio (gear plus tire) should be within a couple percent with the fronts slightly pulling.

Without exactly matching the rolling diameter of the original tires, it's virtually impossible to get the ratio to what it should be. For example, if the factory tires were already at the one end of the size parameter, a minimal amount of difference of rolling diameter in one direction might be too much. While a slight difference in the other may even be a tad better than when it left the factory.

Chim, you want to be using rolling circumference rather than rolling diameter. Since the tire is not a true circle, you cannot use diameter to calculate circumference. The error by using arithmetic & diameter is likely to throw the lead/lag percentage off more than you want.

But if it has R4s on it now and you like the way that they work in 4WD, measuring the rolling circumference on the ground is easy by putting some wet paint splotches on the tread and measuring the distance between paint marks as you drive down a smooth flat road in 2WD. Averaging a few runs helps. I've done it; it works.

BTW, I went from R1s to R3 turfs. Nice soft ride. But rims + tires was sure expensive.
rScotty

 

[chim]

Chim, you want to be using rolling circumference rather than rolling diameter. ......................

You're correct and that is what I was looking at. Don't know why I got off track when I posted. I found RC's within an inch or so of the original tires (around 89"). Without knowing the mechanical ratio of the drive train makes me uncomfortable about choosing replacement tires. It could be better to go an inch longer, but then it could be better to go 2" shorter. There's enough tread left so it isn't something I need to do soon..

 

[rScotty]

You're correct and that is what I was looking at. Don't know why I got off track when I posted. I found RC's within an inch or so of the original tires (around 89"). Without knowing the mechanical ratio of the drive train makes me uncomfortable about choosing replacement tires. It could be better to go an inch longer, but then it could be better to go 2" shorter. There's enough tread left so it isn't something I need to do soon..

Good on the RC. I've done the same thing in conversation myself. It's easy to think of tires as being round, but of course they aren't.

I agree that to do this right, you need to measure what you have. Measure the real RC that you have now and also the mechanical ratio of the drive train. Compare that lead/lag with how much windup you feel that you are getting in the drive train right now. Only then do you have enough info to proceed.

It would be nice to know the original manufacturer's front to rear mechanical ratio and most were good about publishing it in the shop manual. But I'd still measure to be sure.
When I measured the mechanical ratio on my Yanmar 33hp as part of the project to go from R1 to R3s, I came up with a slightly different internal mechanical ratio than the manufacturer's literature said. Very close, but different. That was true for my existing tire's RC as well - that is, my real measurements were slightly different than manufacturer's specifications.
rScotty

 

[Shaneard]

I just put new rear tires on the back of our 4630 ($1,305) went with Firestones. I talked with 4 different tire companies. One told me to stay away from foreign made tires because they won't hold up as long as the Firestones even though the foreign tires were 8 ply and the Firestones are 6 ply. I ask the people that put them on about radials, he said do you drive on the road a lot? I said no, I haul it if I have to go anywhere. He said it's not worth putting radials on then. I sure hope they last 25 years like the ones I took off but I don't see that happening.

 

[searcyfarms]

I have R1 radials, I have R4, I have R3, I have R1 bias, I have SS hwy tread, I had SS no flats, they all have their purpose and design.

IF your ultimate goal is traction R1 radial, if your goal is the least traction and less turf damage = turf - regarding a mix, you are going to get one desired result to be better ( traction ) while your other desired result will be less. There is no perfect combo, that is why I have several different sets for my SS.

if you are wanting mediocre traction R4 - I have never tried an R4 radial ( don't know if they make them ) maybe they are a lil better on traction?

my dad pulls garden tractors, a sharpened R1 will go farther ;-)

I would agree ratios/circumferences are much desired in tractor mechanical wear. I wouldn't risk some desired tiny bit of improved tractor over my transmission/rearend/front differential.

on these small tractors the traction gains would be minimal compared to what you gain on a large tractor, I run my tires WAY under spec as far as PSI because I like a better ride and it might improve my traction a little - substantially probably not - R4s are STIFF!!!! but they are a good compromise in traction and stability and turf wear - the chevron softer style like a zero turn mower are great for fronts on a SCUT I had some of those on my 2210 deere and they were awesome, easy on the grass but great traction - my buddy with his mowing business and grasshopper zero turns put me onto them. they went right on the rims no issues no new rims.

If you want a tire that rides good and gets amazing traction, put an ATV tire on a mower, then u have both!!!!

 

[Oldpath05]

A year after I bought my tractor , told the dealer I wanted to change the front AGs to R4s, he said fine just as long as I change the rear ones to, I ask why he said because of the size difference it will throw off the drive train ratio. Seems like tractor tires are limited to options but when it comes to trucks, Jeeps and atv's there's all kinds of tire selections and configurations.