B7100 HST Rear Tires

[protex28]

I just recently bought a B7100 HST tractor. Tires are very old and definitely need replaced. I know there are a lot of threads already that discuss tires for these older b7100 like tractors, but they always end up getting uber confusing because a bunch of people chime in with different variations and I keep getting lost. So, I’m making a thread specific to the B7100 HST to try to keep things clear.

Just so we’re all on the same page, here’s the tractor data wheel dimensions: https://www.tractordata.com/farm-tractors/005/1/4/5147-kubota-b7100hst-dimensions.html

I’ve got AG tires on it currently, and I want to keep the same style. But, here’s where things get confusing:

1) Tractor data calls for 8.3-16 rears. The tires on there are 8-16. I know that the RC is what really matters, but this tire is so old I can’t find the RC for it (Bridgestone k8702). Additionally, the tractor obviously was not super well maintained, so I don’t trust that the previous owner actually checked to make sure they could use these particular 8-16 instead of the recommended 8.3-16. So, does anyone know what the RC for these should be or how I might find out? Tractordata is wrong. Official size in the WSM is 8-16.

2) I don’t see anything on the valve stem to secure it to the rim. This makes me believe that these are tubeless. Is this a correct assumption? Outside of taking the wheel off, is there any way to be 100% certain? Assuming I want to just go with adding a tube, will I need new rims? Or can I just get a tube for the new tires? Tires are indeed tubeless. This is determined by a fat rubber based stem as opposed to a skinny straight stem or a stem with a bolt to secure it. There are no issues with converting tubeless to tubed.

I know this is a lot so, if I need to clarify anything please let me know.

Edit:
Adding answers to my questions in red for posterity incase anyone else comes looking.

 

[kubotafreak]

If the valve stem is straight without a fat rubber base, it is/has a tube installed. If the valve stem is fat at the base, it is a conventional stem and tubeless. Another type of HD tube can/may have a threaded collar at the base of the stem, again tube installed.

8.3-16, and 8-16 are so close in size they are within the worn circumference differences. I wouldn't be concerned about it especially on such a small machine. One is slightly wider, both should be ~31"

 

[protex28]

If the valve stem is straight without a fat rubber base, it is/has a tube installed. If the valve stem is fat at the base, it is a conventional stem and tubeless. Another type of HD tube can/may have a threaded collar at the base of the stem, again tube installed.

8.3-16, and 8-16 are so close in size they are within the worn circumference differences. I wouldn't be concerned about it especially on such a small machine. One is slightly wider, both should be ~31"

Awesome, thanks. It does look like there’s a fat rubber base on there so, I think it’s tubeless. Glad to know I’m overthinking the tire size, I’ll just go with 8-16 since that seems to be easier to find.

 

[North Idaho Wolfman]

I just recently bought a B7100 HST tractor. Tires are very old and definitely need replaced. I know there are a lot of threads already that discuss tires for these older b7100 like tractors, but they always end up getting uber confusing because a bunch of people chime in with different variations and I keep getting lost. So, I’m making a thread specific to the B7100 HST to try to keep things clear.

Just so we’re all on the same page, here’s the tractor data wheel dimensions: https://www.tractordata.com/farm-tractors/005/1/4/5147-kubota-b7100hst-dimensions.html

I’ve got AG tires on it currently, and I want to keep the same style. But, here’s where things get confusing:

1) Tractor data calls for 8.3-16 rears. The tires on there are 8-16. I know that the RC is what really matters, but this tire is so old I can’t find the RC for it (Bridgestone k8702). Additionally, the tractor obviously was not super well maintained, so I don’t trust that the previous owner actually checked to make sure they could use these particular 8-16 instead of the recommended 8.3-16. So, does anyone know what the RC for these should be or how I might find out?

2) I don’t see anything on the valve stem to secure it to the rim. This makes me believe that these are tubeless. Is this a correct assumption? Outside of taking the wheel off, is there any way to be 100% certain? Assuming I want to just go with adding a tube, will I need new rims? Or can I just get a tube for the new tires?

I know this is a lot so, if I need to clarify anything please let me know.

Tractor Data's, data is WRONG
The B7100 ONLY ever came with 8-16's NEVER 8.3-16

There are 8-16 R1 and there are 8-16 R2 or 8.3-16 R2 (rice)
You want 8-16 R1 (not rice tires)

You can tube a tubeless rim without issue, But why would you want to?

 

[Nicksacco]

Hi Wolf (@North Idaho Wolfman )

Not a tire expert here - but would it seem a good idea tubing a tire (tube type or tubeless) if you were using liquid fill to separate the liquid from the wheel.

I'm curious as to experiences with liquid fill and the types used. A lot of the youtube sites push Rimguard, but I've seen people use windshield washer fluid. I don't know if calcium chloride is used any more.

What kind of experiences do you and others have?

 

[protex28]

Tractor Data's, data is WRONG
The B7100 ONLY ever came with 8-16's NEVER 8.3-16

There are 8-16 R1 and there are 8-16 R2 or 8.3-16 R2 (rice)
You want 8-16 R1 (not rice tires)


View attachment 123777

Thanks. Thats super helpful. Is this information in the WSM? I guess I should actually read the whole thing instead if just piecemeal looking through it.

You can tube a tubeless rim without issue, But why would you want to?

I was under the impression that tubed is a little bit more resilient. But, the main reason was I was having difficulty finding an 8.3 tubeless. 8-16 tubeless abound, though, so I’ll just stick with tubeless.

 

[TheOldHokie]

Hi Wolf (@North Idaho Wolfman )

Not a tire expert here - but would it seem a good idea tubing a tire (tube type or tubeless) if you were using liquid fill to separate the liquid from the wheel.

I'm curious as to experiences with liquid fill and the types used. A lot of the youtube sites push Rimguard, but I've seen people use windshield washer fluid. I don't know if calcium chloride is used any more.

What kind of experiences do you and others have?

I have a B7200 with CaCl in the tubeless rears going on 20 years. Never had a problem.

Messicks filled the rears on my brand new L3901 - mystery fluid but pretty sure its not Rimguard.

70 year old 1951 Ford 8N with tubes and CaCl - fallung apart rotten and leaking like a sieve whem I got it. Now has new tubes and rims and no liquid
Kind of light in the britches....

Dan

 

[SDT]

Tractor Data's, data is WRONG
The B7100 ONLY ever came with 8-16's NEVER 8.3-16

There are 8-16 R1 and there are 8-16 R2 or 8.3-16 R2 (rice)
You want 8-16 R1 (not rice tires)


View attachment 123777

You can tube a tubeless rim without issue, But why would you want to?

What a surprise.

Tractordata is a decent place to start research but the data therein is not to be trusted if accuracy is important.

 

[North Idaho Wolfman]

Thanks. Thats super helpful. Is this information in the WSM? I guess I should actually read the whole thing instead if just piecemeal looking through it.

Yes the info is in the WSM, right in the front part of it.

 

[North Idaho Wolfman]

Hi Wolf (@North Idaho Wolfman )

Not a tire expert here - but would it seem a good idea tubing a tire (tube type or tubeless) if you were using liquid fill to separate the liquid from the wheel.

I'm curious as to experiences with liquid fill and the types used. A lot of the youtube sites push Rimguard, but I've seen people use windshield washer fluid. I don't know if calcium chloride is used any more.

What kind of experiences do you and others have?

I don't like calcium chloride, too many down sides.
Rim guard is good, but pricey, and limited access.
I'm in the camp of RV antifreeze then WW fluid, good weight and much less of a environmental impact and rim damage impact.

 

[protex28]

So, appearently even though the stem was fat at the base it's actually tubed type and not tubeless. Got the tire/tube off and the rims have dirt/rust caked on, and the tubes (especailly the valve) look to be 1 psi short of blowing out. I already purchased tubeless tires, but I'm concerned if I go get a tubeless valve, the tires may not seal on the rims. Is it worth the trouble of putting the tire back together to see if the new tires seal, or should I just cut my losses and get new tubes and move on with my life.

I can come back with pictures after work/tomorrow morning if that would be helpful.

 

[TheOldHokie]

So, appearently even though the stem was fat at the base it's actually tubed type and not tubeless. Got the tire/tube off and the rims have dirt/rust caked on, and the tubes (especailly the valve) look to be 1 psi short of blowing out. I already purchased tubeless tires, but I'm concerned if I go get a tubeless valve, the tires may not seal on the rims. Is it worth the trouble of putting the tire back together to see if the new tires seal, or should I just cut my losses and get new tubes and move on with my life.

I can come back with pictures after work/tomorrow morning if that would be helpful.

Sounds like a question best suited for the tire guy.

Dan

 

[North Idaho Wolfman]

Pictures will help tremendously.

 

[protex28]

Pictures will help tremendously.

I'll get some ASAP.

 

[protex28]

These pictures make it look better than it is. On "wheel_2" there's a pretty significant high spot on the right portion of the wheel in the image.

 

[TheOldHokie]

These pictures make it look better than it is. On "wheel_2" there's a pretty significant high spot on the right portion of the wheel in the image.

If mine they would go to the recycling center.

Dan

 

[North Idaho Wolfman]

Yea, your not going to get a tire to seal to that rim.
Tubes or new rims.

FRONT REAR WHEEL RIM 5.5" x 16" 6 Lug 70000-00028 for KUBOTA Compact Tractor | eBay

(8.3 x 16 Tire). Kubota COMPACT TRACTOR: B1550. Kubota COMPACT TRACTOR: B1700. Kubota COMPACT TRACTOR: B1750. Kubota COMPACT TRACTOR: B2100. Kubota COMPACT TRACTOR: B2400. Kubota COMPACT TRACTOR: B6100.

www.ebay.com

 

[jyoutz]

Calcium chloride strikes again.

 

[protex28]

Calcium chloride strikes again.

yeah, I don’t even think it was that. Unless it was done a really long time ago. No liquid was present in the wheel/tube. I think the tires just went flat for a really long time at some point and the wheels sat in water. Could have been calcium chloride, though.

Thanks for all the advice, everyone. New wheels are on the way.