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Tire change - Just a normal day in Dakar.
- Thread starter Klaus
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Desert Dog
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Hard work! I guess that's why you have three crew!
facteryfmf
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The tire doesn't even look flat
bajaherbie
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dang, look at all those sponsor decals....
off2desert
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Rolling garage, look at all the spares in that open compartment.
John Bitting
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Air bag jack is bitchin. Its funny that guys complain about 39s when they use winches to get these things back in the truck. I guess I will stop complaining about changing 35s in my garage. Wow.
Speed racer
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Apart from the fact that this is backbreaking work it's also very dangerous...
Slippery P
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Gnarly!
TRUKTOR
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I think those tires are XZL 395 -85R -20's , although they could be 24R21's..... Although I don't think so.
The 395's are what are used on MRAP military trucks....and Unimogs, but these might be a Special Dakar version. All commercially available versions of
The XZL have a top speed rating of 55 MPH, And I don't think Michelin would feel good about a bunch of heavy trucks in rough terrain going twice the rated Speed.
Edit : I think those have to be larger than the 395's, and on 24" rims...not 20's.
They are just too big , compared to mine.
These tires with rims are 300 lbs a piece, give or take a few pounds, and getting them up onto the lugs Is a major victory. Jib arms with electric winches to get them on and off the spare rack is the norm.
On my Unimog ( new one, the green one is sold) I run 425 /75r /20 XM 47's, which are a chevron tread AG Tire. They are lighter and more flexible than the XZL's, and not as tall by almost 3".... They weigh 288 Lbs per corner. Changing all 4 of them, in a parking lot by myself with an air gun, and a pallet jack was a royal pain. It drove home the point of what kind of effort would be needed to change A flat out in the rocks or the sand . I have been lucky to Not have had to do that yet.
From what I know , you are not supposed to stack air pillow jacks, and you are supposed to back them up with a jack stand.
Weight ? The current Unimog weighs 13,700 Lbs (semi-empty). The race trucks are probably within 1500 lbs of that, up or down. Hopefully Down.
The 395's are what are used on MRAP military trucks....and Unimogs, but these might be a Special Dakar version. All commercially available versions of
The XZL have a top speed rating of 55 MPH, And I don't think Michelin would feel good about a bunch of heavy trucks in rough terrain going twice the rated Speed.
Edit : I think those have to be larger than the 395's, and on 24" rims...not 20's.
They are just too big , compared to mine.
These tires with rims are 300 lbs a piece, give or take a few pounds, and getting them up onto the lugs Is a major victory. Jib arms with electric winches to get them on and off the spare rack is the norm.
On my Unimog ( new one, the green one is sold) I run 425 /75r /20 XM 47's, which are a chevron tread AG Tire. They are lighter and more flexible than the XZL's, and not as tall by almost 3".... They weigh 288 Lbs per corner. Changing all 4 of them, in a parking lot by myself with an air gun, and a pallet jack was a royal pain. It drove home the point of what kind of effort would be needed to change A flat out in the rocks or the sand . I have been lucky to Not have had to do that yet.
From what I know , you are not supposed to stack air pillow jacks, and you are supposed to back them up with a jack stand.
Weight ? The current Unimog weighs 13,700 Lbs (semi-empty). The race trucks are probably within 1500 lbs of that, up or down. Hopefully Down.
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Speed racer
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This is exactly why I said it was a very dangerous exercise...stacking pillow jacks is a big no, no for sure
Mike321
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How do you use a jack stand in sand during a race? It looked safe to me.
Mike321
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To me, it looks like there's just one spare remaining. But they are about to bury a good spare with a 300 pound flat. Looks like there's room to stand them up side by side?
TRUKTOR
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The reason the flat does not look flat is because they are stiff - the individual
Load ratings range from 11,000 to 15,700 lbs per corner, so One tire is rated to
Carry about the weight of the whole Race truck.
When mounted on the Truck, you can take the air out and they look about the same as when fully
Inflated. Sidewall flex is pretty minimal. The MRAPs, which run the 395/20's,
Weigh between 14 and 18 tons, so a 7 ton Unimog does not get much flex
Out of them.
Michelin is clear that the Speed rating "must not be exceeded", which means
These must be a different version of the XZL than the public can get.
It's possible that they have less plies and more sidewall flex than the normal
XZL.
An 18" square chunk of 3/4" plywood makes a jack stand work in the sand-
I know racing is not safe, but there are pillow jacks that you would not have to
Stack.
Load ratings range from 11,000 to 15,700 lbs per corner, so One tire is rated to
Carry about the weight of the whole Race truck.
When mounted on the Truck, you can take the air out and they look about the same as when fully
Inflated. Sidewall flex is pretty minimal. The MRAPs, which run the 395/20's,
Weigh between 14 and 18 tons, so a 7 ton Unimog does not get much flex
Out of them.
Michelin is clear that the Speed rating "must not be exceeded", which means
These must be a different version of the XZL than the public can get.
It's possible that they have less plies and more sidewall flex than the normal
XZL.
An 18" square chunk of 3/4" plywood makes a jack stand work in the sand-
I know racing is not safe, but there are pillow jacks that you would not have to
Stack.
Short Bus
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I'm kind of surprised they don't have some kind of hydraulic or air jacks in them like the race cars do.
This is the tire that DeRooy is using:
Offroad ORD | Goodyear Truck Tires
He is using the 375/90-22.5
This is the tire that DeRooy is using:
Offroad ORD | Goodyear Truck Tires
He is using the 375/90-22.5
Speed racer
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Automobile racing is a dangerous sport but it can be done safely, don't do anything that will increase the odds of having an accident...
They didn't just stack the jacks, they also stacked three blocks on top of the jacks too...!
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