Rims and Tires for B6100 and B7100

[Guitfiddle]

Hi all,

Struggling to get new shoes for my B6100D

The specs call for:
Turf:
20.5 x 8 - 10 2PR in the front
27 x 8.5 - 15 4PR in the rear

R1:
6 - 12 2PR in the front
7 - 16 4PR in the rear

Currently, it has bigger tires ("turfish") front and rear installed:
23 x 8.50 - 12NHS 4PR in the front (Goodyear Soft Trac)
11-15LT in the rear (Firestone All Terrain)

I went in to see my Kubota dealer, and he recommended the tires that ship with the B2320HSD.

6 - 12 R1 Carlisle front
9.5 x 16 R1 Carlisle rear

The new tires come with new rims. It's cheaper than buying just the tires for some reason. However, the front rims wont work for me, because they are 6 bolt and my B6100D needs 4 bolt. I can work around this, because Kubota still sells the 4 bolt rims I need and they even have them in stock.

The new rear rims wont work either. The bolt pattern and hub spacing are correct, however the lug holes on the new rims are too big. They are 16mm holes vs 14mm lug holes on my current rims. My Kubota dealer can only supply me with 16mm lug rims - all the 16" 14mm lug rims are no longer available. I need to figure out what to do. I'm thinking I need to either:

1. Make/buy some 2mm bushings to take up the slop in the holes.
2. Find some other 16" rims that will fit my 14mm lugs and the 9.5 x 16 tires.

What have you guys done to replace the wheels and tires on the B6100 and B7100 series tractors? I read through a whole bunch of threads on here about people putting on new rims and tires (R1 and R4), and nobody has ever mentioned the 14mm lug size being an issue, yet Kubota can only supply me with rims that have 16mm lug size.

Thanks a bunch in advance for your help!

 

[North Idaho Wolfman]

#1 is it 4wd, if it is then the 9.5x 16 will be too big, RC / Rolling circumference is the key here.
If it's not matched you will do damage to the 4wd system.

 

[85Hokie]

#1 is it 4wd, if it is then the 9.5x 16 will be too big, RC / Rolling circumference is the key here.
If it's not matched you will do damage to the 4wd system.

If he is talking about the tractor in his bio - he does have 4WD ( B6100DT) - and there again he will have problems!

I would suggest bushings, making them or getting them made would be a hell of lot cheaper the playing with rims!

 

[Guitfiddle]

#1 is it 4wd, if it is then the 9.5x 16 will be too big, RC / Rolling circumference is the key here.
If it's not matched you will do damage to the 4wd system.

Hmmm. They would be a matched set from Kubota.

6 - 12 in the front and 9.5 - 16 in the rear.

The specs call for:

6 - 12 front and 7 - 12 rear.

I knew the 9.5 would be wider, but will they also be taller?

 

[North Idaho Wolfman]

Yes they are taller and thus larger RC
Yes they are a match set, matched for a different tractor with a different gear ratio.

8-16 = ~93 RC
9.5-16 = ~99 RC

 

[Jeff19]

I changed my B7200 from turfs to ags. My backs (8-16) RC measures 94 and fronts (6-12) RC measures 73........how dangerous will this be? Thanks

 

[Guitfiddle]

Yes they are taller and thus larger RC
Yes they are a match set, matched for a different tractor with a different gear ratio.

8-16 = ~93 RC
9.5-16 = ~99 RC

Thanks! Wouldn't know the RC for the front, would you? So I can see what the percentage would be? Surprised the dealer would recommend a set that would damage my tractor, but not shocked.

So, still waiting to hear what folks are using for their 6100s and 7100s. There are a lot of threads here about new wheels. What have you found for wheels that will fit and work safely? R1 or R4 if possible, if not then turfs.

Thanks again!

 

[Lil Foot]

I believe e-bay has an implement rim that is a direct replacement for the B7100 rear rim, and I think the B6100 uses the same rim. I think there are a couple of different vendors.
http://www.ebay.com/itm/70000-00028...hash=item35b446ef7e:m:mL6BVnGx8Ol8eMBUrEg0TiA

 

[Guitfiddle]

I believe e-bay has an implement rim that is a direct replacement for the B7100 rear rim, and I think the B6100 uses the same rim. I think there are a couple of different vendors.
http://www.ebay.com/itm/70000-00028...hash=item35b446ef7e:m:mL6BVnGx8Ol8eMBUrEg0TiA

Thanks! That does look like it would fit. I wonder if the lug holes are for 14mm or 16mm lug bolts. I'll ask the seller. Thanks again! Now, I'll need to find some tires.

 

[North Idaho Wolfman]

I changed my B7200 from turfs to ags. My backs (8-16) RC measures 94 and fronts (6-12) RC measures 73........how dangerous will this be? Thanks

You'll be fine, that is what size is supposed to be on it.

 

[Jeff19]

You'll be fine, that is what size is supposed to be on it.

Thank you very much!

 

[Jeff19]

Thanks! That does look like it would fit. I wonder if the lug holes are for 14mm or 16mm lug bolts. I'll ask the seller. Thanks again! Now, I'll need to find some tires.

I bought these same rear wheels from same company on ebay for my B7200. Very fast shipping and a great fit. They weren't very good at answering questions but you can send back for full refund minus shipping.

 

[Guitfiddle]

I bought these same rear wheels from same company on ebay for my B7200. Very fast shipping and a great fit. They weren't very good at answering questions but you can send back for full refund minus shipping.

Thanks Jeff. What size are your lug bolts (14 mm or 16 mm), and what tires did you put on these?

Thanks again!

 

[Jeff19]

Not sure size of lugs. I just went with a pair of Harvest Kings off ebay. Priced good and free shipping. Didn't want to spend a lot in case wheels didn't work.

 

[tiredguy]

Thanks! Wouldn't know the RC for the front, would you? So I can see what the percentage would be? Surprised the dealer would recommend a set that would damage my tractor, but not shocked.

The original 20.5x8-10 rolling circumference is 61 inches.

You're surprised that a "dealer" recommended something else and most of
us are not and why we hang out here asking questions learning from others
to avoid the problems created by the uninformed. I can't tell you why those at the "dealer" don't know what's right from wrong but can tell you for certain it happens far to often.

Another thing to be diligent on your research when switching even though
the "book" says there are other size options is to "do the math" because
quite simply "it ain't always so". It may come with other options and if it
did it probably had different gear ratio front/rear end that allowed them to
use totally different tires.

Lots of info if you do some searching in her to answer you questions.
Al

 

[Guitfiddle]

It may come with other options and if it
did it probably had different gear ratio front/rear end that allowed them to
use totally different tires.

Lots of info if you do some searching in her to answer you questions.
Al

So if my tractor shipped with turfs originally, it would have a different gear ratio than if it shipped with Ags? I can see the sense in that, but I never considered it. I figured they would pick a set of turfs and a set of Ags that would work with one gear ratio. I'm not sure what my tractor shipped with originally.

You are right, a search turns up lots of threads, and over the past two months I have read all of them. None of them have answered my questions enough to place an order on though. A search on 14 mm turns up only my thread.

Thanks Al, your help is greatly appreciated.

 

[Jeff19]

Thanks Jeff. What size are your lug bolts (14 mm or 16 mm), and what tires did you put on these?

Thanks again!

I finally got my aftermarket rear wheels on with 8-16 ags. Also installed the 6-12's on the front and everything seems to work good. I couldn't find anyone to help out with the rear wheels so took a chance and it paid off.

 

[Guitfiddle]

I finally got my aftermarket rear wheels on with 8-16 ags. Also installed the 6-12's on the front and everything seems to work good. I couldn't find anyone to help out with the rear wheels so took a chance and it paid off.

Glad to hear it Jeff! That's excellent. I'm no further ahead in my search. Can't find a set of wheels and tires that will work.

 

[Lil Foot]

What size are your lug bolts (14 mm or 16 mm),

Not sure size of lugs.

For future reference,my '79 B7100 has 14mm studs.

 

[Guitfiddle]

Ok, I found a dealer for tires that can get me the stock Ag tire sizes for my B6100D. I asked him about the RCs for these, and here is his reply:

Ok according to my book
6-12 OD = 23.0 inches
7-16 OD = 29.2 inches

That could be just the overall diameter and not the RC, though I'm not sure what use the overall diameter would be for a tire manufacturer to list in a book.

If that is, or is close to, the RC, that would give me a front/rear ratio of 0.787. How do I know how that compares to the stock tire ratio (which were the same "size")?

Is getting the same size tires close enough?

Thanks!