RTV & Tires

[bordercollie]

I keep between 18 and 20 in my heavy lugged evolutions, and also the oem atv type which are not far from slick- they are my summer/dry weather tires now. When I put the high pressure in my xtrs- they broke down and developed bulges- all 2 sets of them and still had great tread left.

 

[wheezer]

Which kind was it that got the bulges?

 

[bczoom]

You'll want to choose 4 tires that are as close to identical in height as possible. If you have taller tires front to back, you can damage your drivetrain when in 4-wheel drive since the tires will be rotating at the same speed but distance traveled will be different.

Let's say you have 25" tires front and 26" rear:
Since circumference is Pi * diameter:

Front tires 25*3.14 = 78.5" per revolution.
Rear tires 26*3.14 = 81.6" per revolution.

Something is going to have to make up that 3.1"

 

[wheezer]

Now that's interesting right there. I love it when you throw pie around!

Incidentally my brother memorized pi to 15 decimal places. I only got to 9 -- 3.141592653.

Anyhow, back to tires, I had not thought about that difference in circumference. I think I need to check the outside diameter of my two mismatched tires. I bet there is at least some difference, and as you point out, zoom, the difference front to rear is a problem too. I have a lot of research to do.

 

[wheezer]

Here's the scoop: AT489 o/s diameter is 25.5"; Mud Wolf o/s diameter is 25.0"

So, with zoom's computation, I have 25.5x3.14=80.07" on one side and 25.0x3.14=78.5" on the other. That difference of 1.57" has to be going somewhere and putting a strain on the wheels. I need to hurry up and get that new tire.

Bordercollie, I see those Evolutions are pretty expensive, like $150 a piece. I am a fuzz too cheap for that. Since I'm buying wheels too, I need to save a little. I can get an AT489 for $92 and I only have to buy one to have a pair. I'm sure it's not as good a tire but we don't put many hours on our RTV's, particularly with having a his and hers.

 

[bczoom]

I love it when you throw pie around!

Just throwing some pi in your face.

So, with zoom's computation, I have 25.5x3.14=80.07" on one side and 25.0x3.14=78.5" on the other. That difference of 1.57" has to be going somewhere and putting a strain on the wheels. I need to hurry up and get that new tire.

I'd think you would be OK with the 2 different sizes so long as you keep it out of 4WD and don't use the differential lock.

BTW, for best measurement, measure the circumference of the tire instead of the diameter.

Also, you could tweak the air pressure. Put more pressure in the smaller tire and less in the larger and you may be able to equal them out to buy yourself some time. But you may be pushing yourself back to a sloppy ride.

 

[wheezer]

I actually had higher pressure in the larger tire. AND, it's the one that has Max Inflation pressure 7 psi on it (the AT489). Now I'm getting afraid of that AT489. It also says on the tire that it is designed for flotation and not to exceed 25 psi to seat the bead. I'm about to decide to get a couple of 25x11-12 Xtra Tuff brand just to match the front and keep the sizes recommended in the owner's manual. For ATV type tires the manual recommends 25x10-12 front and 25x11-12 rear.

 

[bordercollie]

Which kind was it that got the bulges?

It was the mudlite xtr's that started breaking down. I have pictures on here somewhere... I make my living with the RTV so sprung for the evolutions. They will carry the weight I need. Had a low tire on front and didn't even know it because the sidewalls are tough. Oh shoot, time to go back to work. . Will get back to this tonight.

 

[bordercollie]

I have to add that the evolutions are multi directional so I can swap sides as they wear and get a bit more use out of 'em. I think there are a couple of others ( maybe the bighorns??) that offer the same advantage. I was sad after I spent that amount for those evolutions but they had what I needed>>> Heavy sidewalls, deep lugs , and .. I think they will last longer that the others I had for sure. I have spend a good deal on tires since my first RTV with the WS tires which got me stuck the first time out and then I changed out to the more aggressive types and left the WS on the oem rims in the barn.. Sold the '05 with them on it. I don't buy tires to get a newer model ,but because I have to.. either mine being slick or wires coming out of them- being radials (xtrs) ..

 

[wheezer]

I understand what you mean, bordercollie. You are saving money in the long run with those more durable tires.

 

[wheezer]

After continued study on this tire issue, I find that BOTH of my tires on the rear of my RTV are wrong. Both the AT 489 that I have and the Mud Wolf are rated for 7 psi and only 455 pounds of load. There is an AT 489 rated for 22 psi but its a different part number. Now my question is: What will it hurt to run these two tires on the back of my RTV at 7 psi? Does it simply limit the amount of load I can take or will it eventually tear up something?

 

[TWO GUNS]

My Opinion ..........

Run 'em !!!!

Need to haul more weight, put in a couple of more lbs. .....

Think I run only something like 8-10 lbs ......

 

[wheezer]

Great! Thanks Two Guns.

 

[kobe]

Man, somebody is getting ready for a BIG BBQ. Love that rotator! And I think the fuel supply will make it!

 

[ZZZ2D1]

You could very well tear it up bad...
Tire profiles must be the same which is the measured outside diameter of the tire. Different tire's and pressures change this.
Therefore outside diameter has no constant which results in twisting the powertrain out of sequence - this is bad - for one tire makes more or less turns on the differential which is meant to happen only when turning and not going straight down the road. You are taking a risk of doing extensive damage to your hydrastatic/differential components.

 

[TWO GUNS]

You could very well tear it up bad...
Tire profiles must be the same which is the measured outside diameter of the tire. Different tire's and pressures change this.
Therefore outside diameter has no constant which results in twisting the powertrain out of sequence - this is bad - for one tire makes more or less turns on the differential which is meant to happen only when turning and not going straight down the road. You are taking a risk of doing extensive damage to your hydrastatic/differential components.

......... and I agree with zzz2d1 100 % !!!!

When I said run them. I am saying to run them IF, AND ONLY IF, they are all the same diameter. And that goes for the front tires also. They have to be the same. For when you engage the 4wd, you will tear up more than you can afford to fix ....

If they are different, you will have a mess on your hands, like zzz2d1 stated. Twisting the p0wertrain out of sequence, and yes, he is right, that is bad !!!!

Maybe I should slow down reading ALL the post instead of being in such a hurry .....

 

[TWO GUNS]

You'll want to choose 4 tires that are as close to identical in height as possible. If you have taller tires front to back, you can damage your drivetrain when in 4-wheel drive since the tires will be rotating at the same speed but distance traveled will be different.

Let's say you have 25" tires front and 26" rear:
Since circumference is Pi * diameter:

Front tires 25*3.14 = 78.5" per revolution.
Rear tires 26*3.14 = 81.6" per revolution.

Something is going to have to make up that 3.1"

.......... bczoom,
Sorry, but I just missed your post here. It is a great post. THANKS MUCH FOR SHARING THIS ....

 

[kobe]

R.E. Tires. At the forums suggestion, I tried to find 589s with no luck. After reading (Sibiole?) and talking to Robin, I finally tried the Reapers in 10" & 12". Knowledgable I am not on the RTVs, but have worn out three ATVs and a few off road 4 wheelers and have learned a bit about tires. Have not put the Grims to the test yet in really bad mud, but so far they are excellent. And believe it or not, the ride is about twice as smooth as the original worksites. Even this spring in mostly dry conditions I was having issues with the worksites in 4WD. Two wheel with the Reapers in the same area (back of my property is about 20 to 25 degrees) I have not yet spun a wheel.~~~~~KOBE

 

[ZZZ2D1]

I run Kenda bear claw's and would challange anyone in any conditions.
If you look in previous threads you will see I run 2 different tire types for existing conditions.
Two gun's how in the world would you assume 2 different tires and pressures would ever equate to an ok condition??

 

[TWO GUNS]

Two gun's how in the world would you assume 2 different tires and pressures would ever equate to an ok condition??

like i stated, I read that post way to fast, and didn't really pay attention.
I did not read all post ....
AND, when just glaced at the pictures and the post, mostly looking at the tread design, and just did not take time to read ALL !!!!

I didn't assume anything....

..... and if you will read. I agreed, that ALL tires should be the same.