B7100 - Wheel Spacers - Weights - Filling Tires

phaser

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Recently purchased B7100 4x4 with FEL, ROPS (looking to purchase a 48" box scraper).

I'm a big guy (so high center of gravity), and my entire property is sloped. I've had one almost tip over incident, and that's one to many.

I'm considering 4" rear wheel spacers from here:
http://www.motorsport-tech.com/special/tractor/kubota_s

Plus adding rear wheel weights, and filling rear tires.


Can the axles handle those 4" extensions without breaking?

Any thoughts or reccomendations?
 
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phaser

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You have other options. But no, the spacers will not hurt your axles.
Murphy, Very nice looking B7100!

What size tires front and rear, and did you need to upgrade to a wider wheel?

Would those tire sizes be appropiate for an 4x4 HST?

I guess flipping the rear wheels over for extra width is an option as well.
 
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North Idaho Wolfman

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The B7100 has movable hubs, that will gain you a lot of width, another option is to flip the wheels around.
Another option to add some serious stability is to add another set of tires and make the rear duals. It adds some serious low end weight, traction and width.
I looked into adding duals to mine, but looks like I'm going to go with what I have here right now, It's a set of wide studded snow tires that have the same height as my R1's, I also have a set of real aggressive chains for them too.
 

lsmurphy

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Rears are 9.5x16 and the fronts are 23x8.50x12

There are wheel options and yes you'll need a 8" wide wheel for the rear and a 7" for the front.

Is your a 4 lug or 6 lug in the front?
 

phaser

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Rears are 9.5x16 and the fronts are 23x8.50x12

There are wheel options and yes you'll need a 8" wide wheel for the rear and a 7" for the front.

Is your a 4 lug or 6 lug in the front?
My wheeles are 6 lug all around.

The circumference ratios on those tires would be within spec for a 4x4 HST?

.
 
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phaser

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The B7100 has movable hubs, that will gain you a lot of width, another option is to flip the wheels around.
Another option to add some serious stability is to add another set of tires and make the rear duals. It adds some serious low end weight, traction and width.
I looked into adding duals to mine, but looks like I'm going to go with what I have here right now, It's a set of wide studded snow tires that have the same height as my R1's, I also have a set of real aggressive chains for them too.
Right now my hubs are out to the max. The next step would be to flip the wheels.

Perhaps a silly question, but which would give the most stability, dual wheels or going with the above 9.5x16 rear and the 23x8.50x12 fronts, plus adding 4" spacers, filled tires, and wheel weights?
 
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hodge

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Right now my hubs are out to the max. The next step would be to flip the wheels.

Perhaps a silly question, but which would give the most stability, dual wheels or going with the above 9.5x16 rear and the 23x8.50x12 fronts, plus adding 4" spacers, filled tires, and wheel weights?
When you say 4" spacers, are you talking about cumulative (2" each side), or 4" each? I may be wrong, but that is a lot of leverage, especially if you add weights to the wheels and fluid. You should definitely upgrade the hubs if you go that route. Things might work for a while, but the stock hubs are going to move around and take a toll on your axle shafts with that much weight and leverage.
 

kubotasam

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I run the wheel hubs as far out as they can go. I flipped the wheels around. I have ww fluid in the tires and wheel weights. I agree with Hodge if you push the wheels out 4" farther I am afraid something would break. The axles are pretty strong but I would worry about the casting on the side of the differential case that holds the final drives.
 

lsmurphy

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Weight added to wheels/tires have no effect on the axle, the axle does not carry the weight. Weight to the frame is carried by the axle/hub.

The only effect may be the forces against the axle/hub when moving and stopping but your 7001 isn't going to create enough inertia to do any damage.
 

hodge

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Weight added to wheels/tires have no effect on the axle, the axle does not carry the weight. Weight to the frame is carried by the axle/hub.

The only effect may be the forces against the axle/hub when moving and stopping but your 7001 isn't going to create enough inertia to do any damage.
While the weight doesn't bear on the axle, the leverage imposed by the movement of the tire, compounded by extra weight, mass, and distance from where the hub attaches to the axle will create more load. That setup will not last forever.

Phaser, I would suggest that you do this in increments, and stop when you are comfortable with the stability. You have to strike a balance between what works, and what is least damaging to your tractor, long term.
 
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lsmurphy

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Jeeeeez people........

The weight of the wheel/tire is not an active lever working against the axle. The axle rides the wheel, not the wheel to the axle.
 

phaser

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When you say 4" spacers, are you talking about cumulative (2" each side), or 4" each?
I was thinking 4" each side.

I run the wheel hubs as far out as they can go. I flipped the wheels around. I have ww fluid in the tires and wheel weights. I agree with Hodge if you push the wheels out 4" farther I am afraid something would break. The axles are pretty strong but I would worry about the casting on the side of the differential case that holds the final drives.
That's my concern, and why I'm seeking advice about this.
 

lsmurphy

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My KK tiller weights 569lbs and causes me to float the front end. The rear axles not only carry the ENTIRE weight of the tractor but also the tiller.

Something on the order of 1600lbs with me on it.

And you people are worried about the cause and effect of +/- 100lbs.


Get real folks.
 

phaser

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Jeeeeez people........

The weight of the wheel/tire is not an active lever working against the axle. The axle rides the wheel, not the wheel to the axle.
I understand what your saying when considering just wheel weights, and filling the tires.

But could flipping the tires + 4" spacers each side (8" total) + wider tires, (adding to the overall length to the axles), risk breaking an axle?
 

phaser

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My KK tiller weights 569lbs and causes me to float the front end. The rear axles not only carry the ENTIRE weight of the tractor but also the tiller.

Something on the order of 1600lbs with me on it.

And you people are worried about the cause and effect of +/- 100lbs.


Get real folks.
Good points. And now that I think about it, the 3 point can supposedly lift a little over 1000 lbs, (1/2 ton). That's a significant amount of extra weight on the axles. And I would think there's a significant safety margin built in as well for durability.

.
 
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phaser

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You should definitely upgrade the hubs if you go that route. Things might work for a while, but the stock hubs are going to move around and take a toll on your axle shafts with that much weight and leverage.
Did Kubota ever upgrade the B7100 hubs to the newer design before ending production in 1997?
 

hodge

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Good points. And now that I think about it, the 3 point can supposedly lift a little over 1000 lbs, (1/2 ton). That's a significant amount of extra weight on the axles. And I would think there's a significant safety margin built in as well for durability.

.
You don't operate with that kind of weight 100% of the time. Do it with original, loose hubs, and see what kind of wear you get in a couple of years.
Do what you want- I spoke my mind, and that is how I would handle it on my tractor.
 

phaser

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Phaser, I would suggest that you do this in increments, and stop when you are comfortable with the stability. You have to strike a balance between what works, and what is least damaging to your tractor, long term.
hodge, this is good advice, and I totally agree.