Pics of Super Singles

[spicergear]

The 1400x20's won't fit the rear suspension, this 1550/80R20 XL 'Pilote' is the biggest that clears stock. 45.5x15.5 or 46x16 depending on who measures. Same size as 395/85R20 XML's like M1075 runs on his pumper and I run on my M715.
I didn't have a quarter to use for size reference so I used other objects. Oh, 225Lbs per XL.

 

[M1075]

Tom, when are we gonna get to see them on old blue? No, not that one.

 

[spicergear]

Well after late winter's wife conundrum, leading to present large single income mortgage, and throwing in TTC...I've just about got the scratch saved to get the plates cut for the 5 ton 20 bolt beadlocks. Oh...heh,heh...and that sharp looking bike in the pics is my (was my) 2000 Suzuki Hayabusa(fastest production bike ever released to the public, 196mph stock) that was destroyed by a 4' tall 81 year old lady (Yoda's mom) when she yanked out of a driveway and picked me off Saturday of the 4th of July weekend. Totalled her car, totalled my beautiful bike, I bailed last minute and cleared her car then got the sun lovin' tar beat out of me tumbling down the road. I guess in short...I've been a little busy.

 

[Lee Alessi]

i dont get the guy the claims the xl has poor wet weather traction. I have driven XL's, BFG AT's and NDT's. In louisiana we dont get snow, but boy do we get rain. On my m715 the XL's are the best followed by BFG All Terrain and last the NDT tires. I call NDT's big wheel tires (like the plastic toy wheels that slide easily)

IIRC the guy who bashed the xl's was NOT running them on a deuce, or application heavy vehicle, but a civilian vehicle. Overinflated tires on a very light truck will suck irregardless of tread.

 

[M1075]

Tom, glad you are okay. Too bad you weren't driving the duece! That 5ton winch might have plowed the way.

MC, I agree. I'll keep my XMLs over NDCCs anyday.

 

[Lee Alessi]

http://cgi.govliquidation.com/auction/view?id=619145&convertTo=USD

#8 1100x20 xl's in IL

 

[Lee Alessi]

http://cgi.govliquidation.com/auction/view?id=638040&convertTo=USD

12 1100x20's xl's in TX

 

[cranetruck]

I grant you that.
What about DRY pavement traction? I started a thread in the "Deuce" section, but didn't get any response.

 

[Lee Alessi]

hmmm, i never ran the ndt's with my diesel, but heres my experiance.

the ndt's vs michelin xl's on dry pavement in a stock m715 were NO comparison. the xl's are very grippy. you can feel the difference turning the front wheels, turning the truck and accelerating under a load

now xl's vs bfg all terrain tires is a more fair comparison. the bfg all terrains have LESS wet and dry traction on paement. i dont know why. i spin the bfg's in both conditions MUCH easier. thats the reaon i have been entertaining a switch to michelin or good year radials.

 

[cranetruck]

I was thinking about the slicks used by drag racers. A tire with many "moving parts" will also get hotter on dry pavement, limiting its top speed.
Below is an image of my left front after about two hours at 50+ mph on dry pavement. It's an 11.00-20 with a TP of 72 psi.

 

[Lee Alessi]

heat, according to a recent argument i had is more of a product of flex. the compression/rebound of the tire generates the heat. if NDT tires were so good, then why the proliferation of michelins? bias ply tires generate more heat than radials by design. tire design has grown exponentially these last few decades. an NDT is at least 60 year old design and technology. few if any vehicles travelled at 60~70mph when ndts were made. i mean convoy speed is STILL 50~55mph. give or take a few

 

[Wick246]

Wouldn't the NDT's dry pavement traction limitation be the harder rubber compound used? They would probably last longer though.

 

[cranetruck]

Age of a design has nothing to do with its utility. I believe a lot of thinking went into the NDCC tires.
And they are still made today.
An offroad tire should be self cleaning, just look at tractor tires, that design hasn't changed in 75 or more years. The Michelin XL tread pattern has "traps" in it for mud and snow to get caught in.
Being non-directional is a feature.
Tough bias ply sidewalls is a feature for offroad and suitable for tire chains and airing down is possible with the inner tube.
Would be interesting to see the spec requirements for the original military tires that led to the NDCC and NDT tires.

The Michelins are made for offroad use and have rather low max speed spec, about 55-65 mph.


Below is a copy/paste of a response on the mil-veh list:

From : Sarge <micdunn@ev1.net>
Reply-To : "Sarge" <micdunn@ev1.net>
Sent : Tuesday, June 21, 2005 11:59 AM
To : "Military Vehicles Mailing List" <mil-veh@mil-veh.org>, "Bjorn Brandstedt" <super_deuce@hotmail.com>
Subject : Re: [MV] Wet pavement traction, deuce tires


Bjorn, I know that when you look at NDCC's, the natural assumption would be
that they handle and brake poorly on wet roads.
In the 1990's (when I was active duty) the military had multiple accidents
concerning 5-ton trucks, the -900 series, that would skid on wet roads when
the brakes were applied heavily. The number of accidents was so great that a
study was commisioned to find a safe fix. A Google search might find you the
results of this study.
A temporary stopgap measure was to limit -900 series trucks to 35 mph.
As many on this list already know, the -900 series 5 tons came with two
different wheel/tire combinations.
You had a choice between 10 tires with the duallies on the back, 11.00-20's
NDCC's if I remember correctly.
The other choice was six super singles, 14.00-20's, definitely not NDCC's.
The punchline of this story is.....
The wet skidding problem was limited to trucks fitted with the 14.00-20's
!!!
I don't think you will have any problems with the deuce NDCC's.
If you do, you can sue me!
-Sarge
PS. I'm broke.

----- Original Message -----
From: "Bjorn Brandstedt" <super_deuce@hotmail.com>
To: "Military Vehicles Mailing List" <mil-veh@mil-veh.org>
Sent: Tuesday, June 21, 2005 4:21 AM
Subject: [MV] Wet pavement traction, deuce tires


> Is there an index, number or an established methode to measure wet
pavement
> traction for commonly used deuce tires? We know the radials are far better
> than the bias ply NDCC's, but what are the numbers? What about siped
NDCC's?
> The measurement should apply to new and used (say 50%) tires.
>
> On long road trips, it's not possible to count on nice dry weather and the
> tires do become a safety factor.
>
> Any tire experts out there in MV-land?
>
> Thanks,
>
>

 

[Lee Alessi]

yes, i definitly blame the compunf itself. but apparently 3000~7000miles is about all NDT's are good for

 

[cranetruck]

The image of my front tire shown a few posts above has over 5,000 miles on it at the time of that photo. It wears about 1/32/1,000 miles, I figure it's good for at least 15,000 miles. You have to adjust the pressure for max tire to ground contact. For 900-20 tires use 60 psi in the front and 40 in the rear with duals. That's different from the manual, but makes more sense to me.
With about 7,000 miles on them, they now measure about 15/32 (new they are about 23/32).
The front tires are beginning to show more wear on the outside at this time. It's about 14/32 on the outside and 16/32 on the inside.

 

[spicergear]

The biggest difference with NDT's compared to XL's is that the XL does not have a full center rib allowing it to have tread biting edges there and allowing the tire to bite down in and not just spin slick on top. I had a set of Goodyear Xtra Grip that looked to be a great tire, but again, still a very full center tread not allowing it to sink in. I grooved the center of them and the difference was night and day!!! NDT's are okay offroad until you spin them...you're screwed after that. They ball up badly and nobody running them has the wheel speed to clean them. XL's also have a flat tread pattern that helps contact area. I had a set of 1100x16 XL's on my M715 for a while, like Lee, and I grooved each tread block giving the tire twice as many biting edges. There was a noticable difference there too.

 

[M1075]

I was intrigued with the Sarge's comment, so I looked into it. From what I have seen so far, I'm not sure he has his facts straight.

"The accident scenario for all M939 trucks occurs during panic stop situations and is worsened on wet pavement. In panic stop situations the trucks wheels lock up causing engine stall. This causes loss of power steering resulting in uncontrolled skidding creating accident and roll-over situations. Extensive testing of ABS for this truck has shown that ABS will eliminate 100% of the engine stalls and wheel lock-up regardless of the skill level of the drivers. The accident scenario for M939 basic vehicles with NDCC tires occurs during panic stop situations on wet pavement. The front wheels lock up, the NDCC bias tires react like ice skates and stopping distance is increased by 245-320 feet over trucks with radial tires. The M939 truck is expected to support the Army's transformation effort through FY30. Recently the program looked at removing radial tire applications to avoid cost. Recent test data concludes that ABS with NDCC tires is a deadly combination. The tires react like ice skates on wet roads and braking distance is increased by 245 to 320 feet over a truck with radial tires and the ABS kit installed. Once the ABS kit and radial tires are installed, SOUM 98-07 can be lifted, allowing the vehicles to once more be capable of safe operation up to their required operational capability and full mission requirements.

The nondirectional cross country (NDCC) tire design on the M939 basic truck was engineered for cross-country applications prior to World War II. Changes in vehicle speeds, road construction, mission requirements, as well as advances in tire technology have made this NDCC bias tire obsolete and unsafe. This modification will change the tires from the current bias ply NDCC tire to a radial tire designed for on/off road. Recent improvement in radial tire design will provide better traction and mobility, which will enhance system safety."

 

[cranetruck]

I agree that the NDCC's are no good on wet pavement.

 

[cranetruck]

Spicergear, do you have any hints on grooving the tires, depth distance apart etc. Images?
I'm waiting for a grooving tool, should arrive at any time.

 

[spicergear]

If you're not going to be seriously offroading, like only occasional weekend warrior stuff, I'd just cut them with a single 5/16-3/8" wide by 3/8-1/2" depth and just go across the tread block. I did a smaller set of XL's and did diagonal cuts for better offroad/angled traction. My XML's on Velvet are all cut across the tread with the angle of the tread which is what I'd suggest for the larger XL's. Cutting the big tread blocks not only give another set of biting edges but it also allows the tread to be more flexible and engulf a rock instead of just driving up onto it.
Goodyear 1100x20 Custom Xtra Grips

1100x16 XL's

395/85R20 XML's on Velvet...same what I'd cut a BIG XL.