/pine
Super Star Member
- Joined
- Mar 4, 2009
- Messages
- 15,059
Tire help
- Thread starter bikerdib
- Start date
Yep, you are right; that's the point I'm trying to get across. Not that you should adjust the pressure every time the load is changed but that the rolling circumference is already affected by different loads and different inflation pressures, even with the OEM, original tire.
Again, from my direct experience with the tire I mounted, because of stiffer sidewall or belt construction or whatever, the Carlisle seems to be much less affected by loads than the Firestone; it doesn't compress as much when inflated to the same pressures. This should mean the Carlisle will stay closer to the same rolling circumference when under load and that would mean it stays closer to the unloaded rolling circumference of the Firestone than the Firestone did when carrying a load. Damm, even my head is spinning already. :laughing:
I repeat, I'm not trying to talk you into the Carlisle. I'm just saying that unless you manage to find the exact tire you now have, even if the manufacturer gives the rolling circumference you won't know what load was used to get that info so you still might not get the exact same rolling circumference as the Firestone (for all this discussion, I'm assuming the Firestone is the original tire you have on your tractor).
Well, no; he didn't use the Carlisle product I did. He used a 20X8-10 and the All Trail doesn't even come in that size.
Good find. Dang it, in all my web searches for a 21X8-10 that website never came up. That's what I get for using Google. I know Bridgestone and Firestone are connected somehow. Even the product code is the same, G-2 (Firestone was TL G-2). The Bridgestone site doesn't give the load capacity but the overall diameter (I guess they mean mounted) and static load radius are the same as the old Firestone so I have to wonder if it is not the same tire, just re-badged.
How did you find that website? Wonder what shipping would be from Australia on 2 tires? I ask that because I bet no dealer here in the US has access to that tire.
OK, I did a search for Bridgestone here in America. When I clicked on the link for Agriculture tires, the Firestone website came up. :mur:
I had already found that Europe can still get the tire we need, and now we know Australia can also. How about us poor Americans, can't we get some luvin' ...
I had already found that Europe can still get the tire we need, and now we know Australia can also. How about us poor Americans, can't we get some luvin' ...
/pine
Super Star Member
- Joined
- Mar 4, 2009
- Messages
- 15,059
/pine
Super Star Member
- Joined
- Mar 4, 2009
- Messages
- 15,059
ditto...
thanks for all the effort and feedback...and good luck..
it will probably be next spring before I do "something" about tires...
Ah, the "nhs" added to your search string; I didn't put that in.
Again, if you find a source here in the US, let me know. If I do, I'll post here.
Who knows, I might feel energetic one day and put the Firestones back on and do an actual rolling circumference comparison.
Again, if you find a source here in the US, let me know. If I do, I'll post here.
Who knows, I might feel energetic one day and put the Firestones back on and do an actual rolling circumference comparison.
kendive
Bronze Member
- Joined
- Nov 1, 2009
- Messages
- 74
Now I am looking for 21x8.00-10nhs for my 2005 B7510 Kubota I just got used...
Calling around to the local firestone dealers for AG tires.
All I can say is good luck Kendive.
Because now I have to give an update.
I finally got a little free time so I decided to go through the trouble of measuring the ACTUAL rolling circumference of the Carlisle All Trail vs the Firestone Turf & Field. Luckily, I mount my own tires using a manual tire changer so I was able to do this experiment at no cost other than a sore back (hey, I'm 54 years old, cut me some slack) and some time.
First I checked the air pressure in the Carlisle I had already mounted. 28 psi is where I run these tires on the tractor. Used a level to put a mark at the top and bottom of the tire (vertically level) then a mark on the concrete at the bottom of the level. Rolled the tractor forward till the marks went one full revolution and came to vertically level again, then put a mark on the concrete. Measured the distance between marks (which is of course the rolling circumference). The Carlisle have a loaded (please note I have a FEL installed) rolling circumference of 60 inches.
I removed one of the wheels, dis-mounted the Carlisle, mounted the old OEM Firestone I had recently taken off. Put the wheel back on the tractor with 25 psi in the tire. Used the level to duplicate the way I made the marks again. Measured between the marks and found out the Firestones have a loaded rolling circumference of 62 inches.
Now I'm a little surprised at the Firestones because the Firestone website specifies a rolling circumference of 61 inches. This means we can't even go by the info provided by the tire manufacturer.
Now I have to eat my words because I decided that was too much difference. I took the other Carlisle off and I'm back to running the dry rotted Firestones for now. Looks like I may be back to square one of getting all four wheels and tires replaced with R1s. This doesn't really bother me too much because I could use the extra traction anyway. But for those of you that need turfs, I can't recommend the Carlisle All Trail like I originally thought (unless you never use 4X4).
Because now I have to give an update.
I finally got a little free time so I decided to go through the trouble of measuring the ACTUAL rolling circumference of the Carlisle All Trail vs the Firestone Turf & Field. Luckily, I mount my own tires using a manual tire changer so I was able to do this experiment at no cost other than a sore back (hey, I'm 54 years old, cut me some slack) and some time.
First I checked the air pressure in the Carlisle I had already mounted. 28 psi is where I run these tires on the tractor. Used a level to put a mark at the top and bottom of the tire (vertically level) then a mark on the concrete at the bottom of the level. Rolled the tractor forward till the marks went one full revolution and came to vertically level again, then put a mark on the concrete. Measured the distance between marks (which is of course the rolling circumference). The Carlisle have a loaded (please note I have a FEL installed) rolling circumference of 60 inches.
I removed one of the wheels, dis-mounted the Carlisle, mounted the old OEM Firestone I had recently taken off. Put the wheel back on the tractor with 25 psi in the tire. Used the level to duplicate the way I made the marks again. Measured between the marks and found out the Firestones have a loaded rolling circumference of 62 inches.
Now I'm a little surprised at the Firestones because the Firestone website specifies a rolling circumference of 61 inches. This means we can't even go by the info provided by the tire manufacturer.
Now I have to eat my words because I decided that was too much difference. I took the other Carlisle off and I'm back to running the dry rotted Firestones for now. Looks like I may be back to square one of getting all four wheels and tires replaced with R1s. This doesn't really bother me too much because I could use the extra traction anyway. But for those of you that need turfs, I can't recommend the Carlisle All Trail like I originally thought (unless you never use 4X4).
rus_geek
Gold Member
Might be too late to run another test, without a lot of work, but I wonder how much the rolling circumference changes with various loads in the FEL? If the Carlisle indeed has a stiffer sidewall, I would expect less reduction in the rolling circumference than the OEM tire.
Any idea what the gear ratio is between the front and rear to give you the "proper" rolling circumference? Or measure the rolling circumference twice. Once with the fronts locked in and once not. Might have to test on wet concrete to let the fronts slip if the ratio is "wrong."
-rus-
Any idea what the gear ratio is between the front and rear to give you the "proper" rolling circumference? Or measure the rolling circumference twice. Once with the fronts locked in and once not. Might have to test on wet concrete to let the fronts slip if the ratio is "wrong."
-rus-