Mixing R1 and R4 tires. Already read many posted. Here's some more info on possibles

corleone · Oct 15, 2015

Hello,

I've been reading as many posts on the topic of mixing R1 and R4 tires. Specifically, I'm interested in running an R1 rear with R4 front. From the Titan data book, I looked up tire data on both. I have a 2013 DK45SE, so these numbers are specific to the tires I can run.

R1 tires
Front 10x16.5/6 Diameter - 30.4", Rolling Circ. - 91", Tread depth - 21/32" (0.65625"). Rolling circ minus tread depth - 29.0875"
Rear 14.9x24/8 Diameter - 48.9", Rolling Circ. - 145", Tread depth - 32/32" (1"). Rolling circ minus tread depth - 46.9"

Ratio of front to rear rolling circ. - 0.62758"
Taking into account tread depth. Ratio of front to rear rolling circ (minus tread) - 0.62020"

R4 tires
Front 8x16/6 Diameter - 30.5, Rolling Circ. - 91", Tread depth - 31/32" (0.96875"). Rolling circ. minus tread depth - 28.3625"
Rear 13.6x24/6 Diameter - 47.9", Rolling Circ. - 143, Tread depth - 46/32" (1.4375"). Rolling circ minus tread depth - 45.0250"

Ratio of front to rear rolling circ. - 0.63636"
Taking into account tread depth. Ratio of front to rear rolling circ (minus tread) - 0.63437"

When attempting to determine an R1 tire to use with the R4 front - what needs to be taken into account? ...is it just the rolling circumference? ...or the bearing surface below the tread (rolling circ. minus tread)?

Both the R1 and R4 front tires listed above have a rolling circ. of 91". If that was all that mattered, they should be okay to swap back and forth without any issues. I assume it's more challenging than than. And I don't really know the answers either.

I run a FEL and I would like to keep the R4 front tires for this reason. My land gets really muddy with thick sticky clay so I'd like to have the R1 for that as well as extra grip for ground-engaging tools.

Am I drifting into areas that are better to avoid? I don't need to be snapping u-joints or worse...

But this whole problem seems like it should be easy to solve unless the answer is to use a tire that doesn't exist (which would make it all a little difficult).

I'm looking for any/all opinions on this issue. Thank you all for your time.

Garycw · Oct 15, 2015

I have s fel and now deck. I thought about doing just the opposite. R4's on rear with turfs in front. Decided to just go with all R4's

oldpilgrim · Oct 15, 2015

Don't forget to check the wheel width as R4's generally take a wider wheel.

Sounds like a costly solution to a pretty non existent problem.

VictorW · Oct 15, 2015

Rolling circumference at tread is what you have to deal with. I think you'd be fine switching to R1 rears. Varying air pressure in the tires along with tread wear will also make changes as much or a little more than the differences you have calculated. For example, my prior 4wd truck had from factory, 4.10 read axle ratio while the front was 4.09. Normally, any 4wd vehicle or equipment has the fronts with slightly more ground speed than the rears. The tires were to be the same all around and I had run from the factory 31" dia. tires all the way to 38.5" dia. tires on all four. Just this diameter difference would have made the rotational ratio grow with the larger tires and there was never a problem. The only problem you'll have is getting new rims and center disks for the rear R1 tires.

corleone · Oct 16, 2015

Thank you all for the feedback.

Regarding the expense - it's less expensive to replace only rear tires (with new rims and disks) that to buy four new tires and rim/disk sets (to switch from current R4's to R1's). But this really isn't about cost as much as functionality. I would like the R4 fronts for wider loader support but the R1 rears for high traction.

I might be making a bigger deal of the issue with an FEL and R1 front tires... I have heard stories about the thinner R1 having issues with loader work, but I haven't seen it personally yet. I can't imagine that all tractors with FELs run R4 tires, so maybe I'm making trouble for no real reason as all. I mean I could go to all R1 tires/rims and just move on down the path. Does anyone have personal experience with R1 front tires on a tractor with FEL?

IndyIan · Oct 20, 2015

I have R1's and the fronts are fine for loader work. I was just cleaning out the manure in our sloped barn yard and even the R1's needed some help from the rear brakes to turn in the greasy muck. The tires are fine as long as you keep a reasonable tire pressure in them.
Also I believe all the DK's had the same rear rims and wheels so switching between tire types isn't too expensive.

MMagis · Oct 20, 2015

corleone said:
Thank you all for the feedback.

Regarding the expense - it's less expensive to replace only rear tires (with new rims and disks) that to buy four new tires and rim/disk sets (to switch from current R4's to R1's). But this really isn't about cost as much as functionality. I would like the R4 fronts for wider loader support but the R1 rears for high traction.

I might be making a bigger deal of the issue with an FEL and R1 front tires... I have heard stories about the thinner R1 having issues with loader work, but I haven't seen it personally yet. I can't imagine that all tractors with FELs run R4 tires, so maybe I'm making trouble for no real reason as all. I mean I could go to all R1 tires/rims and just move on down the path. Does anyone have personal experience with R1 front tires on a tractor with FEL?

You are. It’s a non issue unless you’re running on concrete all day, every day. The stories you heard were likely on this board, where it seems a large number of members have nothing to do but sit around and overthink things. Heck, there’s a thread here that’s made it to 9 pages and counting where a fella simply asks about what lawn mower to buy.
There are thousands upon thousands of tractors out there with R1s and an FEL. In fact, other than the overgrown lawn mower market, it’s standard issue.

ozley · Oct 20, 2015

You are making a deal of this. I have R1's with a loader an never had a problem with the R1's moving round bales.

TripleR · Oct 20, 2015

We have run R1s on our M8540 for 5 years without problems often hauling full buckets of wer to muddy dirt, just keep them inflated per manual specs.

corleone · Oct 21, 2015

I've heard it all depends on the size of the tractor, too. Larger tractors have larger R1 front tires. My Kioti DK45SE is right on the edge of having R1 too small for heavy loader work. So I guess I was wondering if there are any other people running R1 on 45hp or smaller tractors with FELs that have or have not experienced any issues with this setup.

Thanks,
Adam