R1 to R4 tires on a Kubota L4400?

   / R1 to R4 tires on a Kubota L4400? #1  

cpainter

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Dec 6, 2018
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Location
Central Texas
Tractor
Kubota L4400
Guys, the original rear tires are about shot on my 2011 Kubota L4400. The original tires are R1's: Front: 8.3-16, Rear: 14.9-24. I live in a rocky area of central Texas and the rocks tear up the tread very quick. I'm thinking that industrial tread would hold up better. What would you fellas recommend?
 
   / R1 to R4 tires on a Kubota L4400? #2  
R1 ag tires are four ply.

R4 industrial tires are at least six ply. 50% tougher. Some traction loss relative to R1's pulling over soft or moist ground. Not much traction difference pulling over adobe brick. (Eight and 10 ply R4 tires are fairly available.)

You will need replacement rims to fit less tall R4 tires.
 
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   / R1 to R4 tires on a Kubota L4400? #3  
You can get Ag/R1 tires with more ply, 6, 8, and 10 ply. Do you need help with mud (because R4 suk bad in muddy areas). Industrial/ R4 are pretty tough with rocks...

There is also now R14's but I don't know anything about them...
 
   / R1 to R4 tires on a Kubota L4400? #4  
You can get a 14.9-24 in the R4 class of tire how the loaded radius compares to the R1 I didn't look up and then it would be a matter of getting the correct height tire to match up with the rears.
 
   / R1 to R4 tires on a Kubota L4400?
  • Thread Starter
#5  
Ok, Here's what I found for the size industrials that would have come on it:

1695243846955.png


Where can I find info on the loaded radiuseseses of different tires?
 
   / R1 to R4 tires on a Kubota L4400? #6  
Most tire manufactures have a very good data table for there tires;
this link is to a Titan tire web page that has all of there 14.9-24 tires, R1, R4's and even R14's;
Products

a screen shot of the page, clicking on an item in the left column will take you to a detail of that tire,
1695248596542.png
 
   / R1 to R4 tires on a Kubota L4400? #7  
Ok, Here's what I found for the size industrials that would have come on it:

View attachment 822361

Where can I find info on the loaded radiuseseses of different tires?
To match existing 4wd internal gearing you want to match the existing distance traveled by the front and rear tires. To do that, the spec you want is" loaded diameter", not loaded radius. For oval shapes - not circular - these loaded diameter & radius are entirely different types of measurements, not related, & used for different reasons.
Most of the online tire catalogues will list loaded diameter.
 
   / R1 to R4 tires on a Kubota L4400?
  • Thread Starter
#8  
To match existing 4wd internal gearing you want to match the existing distance traveled by the front and rear tires. To do that, the spec you want is" loaded diameter", not loaded radius. For oval shapes - not circular - these loaded diameter & radius are entirely different types of measurements, not related, & used for different reasons.
Most of the online tire catalogues will list loaded diameter.

So, keeping the ratios of mounted diameter the same won't keep me out of trouble?
 
   / R1 to R4 tires on a Kubota L4400? #9  
So, keeping the ratios of mounted diameter the same won't keep me out of trouble?
Well, that's yet another spec.
My guess is that "mounted diameter" would be measured with no weight on the tires.

We are just guessing now, and nothing wrong with that... but my guess is that keeping the front to rear "mounted diameter" ratio the same for the new R4 as it was for the old R1s would be better than not paying attention to the ratios at all.

I assume you are going to do fronts and rears both... and that you already have figured whether the swap will require different wheel rims on both ends as well as tires. I've done a couple of swaps now.

Easiest thing would be to swap with another owner wanting to go the other way. I really like the tougher R4s. Also, R4s run higher pressures than R1s. So it is a stiffer sidewall running more pressure and with a larger wider footprint. More stable on hills, with noticibly less traction in snow and mud but more traction on hard pack dirt and in the rough.

rScotty
 
   / R1 to R4 tires on a Kubota L4400?
  • Thread Starter
#10  
Well, that's yet another spec.
My guess is that "mounted diameter" would be measured with no weight on the tires.

We are just guessing now, and nothing wrong with that... but my guess is that keeping the front to rear "mounted diameter" ratio the same for the new R4 as it was for the old R1s would be better than not paying attention to the ratios at all.

I assume you are going to do fronts and rears both... and that you already have figured whether the swap will require different wheel rims on both ends as well as tires. I've done a couple of swaps now.

Easiest thing would be to swap with another owner wanting to go the other way. I really like the tougher R4s. Also, R4s run higher pressures than R1s. So it is a stiffer sidewall running more pressure and with a larger wider footprint. More stable on hills, with noticibly less traction in snow and mud but more traction on hard pack dirt and in the rough.

rScotty

I'm thinking with the following choices, I could maybe do front and back at separate times and be ok...especially if I use 4x4 sparingly on loose surfaces. The rocks where I live take chunks out of the tires, so I'm thinking more rubber contacting the ground, lowering contact pressure, might be a good thing.

1695260711032.png
 
 
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