CMP tyre manufacturers

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Development during the war

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More pages

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Last page about tires

[Hanno Spoelstra]

Two 15-cwt rims I picked up recently have American made “Kant Slip” 9.00-16 W /|\ D tyres FOR BRITISH WHEELS made by Kelly Springfield Tyre Co. on them.

They are a proper NDMS bar grip, and not a retread. I have not been able to find a date on them. The American Kelly-Springfield Tire Company was founded in 1894. It was acquired in 1935 by the Goodyear Tire and Rubber Company, who maintained it as a subsidiary until 1999 when it was integrated into Goodyear North America. It continues today as a major brand under Goodyear. So they could have been made anytime during the past.

Could it be the US supplied tyres for British wheels under Lend-Lease? Or would the US supply European MDAP recipients after WW2 with tyres made for their ex-Canadian equipment?

[Hanno Spoelstra]

I had those Kelly tyres taken off the rims and they yielded some nice flaps marked “Goodyear | Made In Canada | for 16” rim” and tubes marked “NCD | W/|\D | Goodyear Made in Canada | 9.00-16 Heavy Duty | Do Not Use in RF Casings”.

[m606paz]

Sieberling Special Service 10.50 x 20

[Keith Brooker]

This is still on my limber that i have just bought.

[m606paz]

Firestone CC Ground Grip

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Ford Factory - Good Year Tires

[Lynn Eades]

Thanks Mariano for posting this article. I found it very interesting.
How many of you have experienced a broken spring? I have had one (off road in my 3/4 ton WC Dodge) To break 2400 springs in tyre testing indicates some arduous testing. Its hard to imagine all that and the back aches that went with the day to day driving involved.

[Hanno Spoelstra]

Original Goodyear 7:00-20 All Weather tyre Made In Canada as fitted to my Canadian made 20-cwt trailer.

[Hanno Spoelstra]

Another Goodyear All Weather tyre, this time a 10.50-16 still fitted to a CMP truck somewhere in the desert.
Source: Fliegel Jezerniczky

[Jacques Reed]

Hi Hanno,

I have posted some of these before at various places but worth putting them all together in one place.
These are NOS 9.00 x 16" Dunlop Trak Grips made in Australia. Too rare and old to use so I have relegated them to display only. Purchased 5 of them in the nineties from a business 2 km from home.
Note the DD broad arrow on the casing and the "To fit BRITISH wheels"
Hope this is of some interest.

Cheers,

[Lynn Eades]

Here's one on a Dodge WC wheel.

[Lynn Eades]

Sorry, I missed the main bit. It's a Good Year Sure Grip. Being a Runflat, shes a heavy b_tch! By the way, It says under the "sure grip" "Made in U.S.A."

[Jacques Reed]

Lynn's run flat tyre photo reminded me:

Just for interest, here is a run flat insert for a 9.00 x 16 tyre made by Firestone in Canada. It may be of interest to those who never saw one in the flesh.

Had it for sale, but no interest was shown in it so sadly it will go to the recyclers soon. Sometimes you just got to let things go.

Cheers,

[David Dunlop]

Interesting, Jacques.

I always thought a run flat was a single cast tyre with a narrow core.

Wonder how much fun it was getting that insert in and out of a standard CMP tyre?

David

[Lynn Eades]

David the bead needs to be clamped otherwise when the pressure drops to zero the wheel starts to rotate inside the tyre. Some runflats (very heavy) were filled with soft (red) rubber. The metal bead locks in the Dodge wheel (see the thread about modifying CMP rims) has a hinge that folds back on its self (to allow insertion into the tyre) The metal ones probably came along as a result of the rubber shortage. The jeep ones are a pressed steel ring.

[Hanno Spoelstra]

Originally Posted by Owen Evans

For reference, An old Dominion Royal 'Trak Master' off my C15. Not so easy to read, so here goes:

Part 1/2: "Lukáš Lukáš" in the Czech Republic found a set of Dominion Royal Trak Master tyres recently. They are still in excellent condition showing many interesting details:




"DOMINION ROYAL
DOMINION RUBBER COMPANY
MADE IN CANADA
PATENTED CANADA"





"TRAK MASTER"

[Hanno Spoelstra]

Part 2/2:

"FOR BRITISH WHEELS
9.00 - 16
10 PLY-PLUS
2 SHOCK PADS"




And this I have never seen before:

"FOR 1 1/2 [degree] TAPER RIM"




"S2"

[Mike Kelly]

Originally Posted by Hanno Spoelstra

And this I have never seen before:

I've not seen that marking myself. Interesting it is 1 and 1/2 degrees. When looking at the British divided rims, the two halves have a pretty flat or level appearance, but apparently there is a 1 and 1/2 degree slope there.

The American system has tires that have the steeper bead angle , I believe this follows on from the normal commercial tire designs of that period.

Some people have reported as having no trouble with fitting the newer recently made ( Chinese ) tyres onto the British or CMP rims so it may be the case that some of the individual brands are allowing for the different tolerances. I spotted a CMP at Corowa with the Chinese tyres on it and spoke to the guy at length about tyres , he made no mention of having trouble with the fitting. He drove the truck across the Nullabor all the way from Geraldton.

Apparently the CMP C8A six stud rims will accept anything - US or British.

[David Herbert]

I wonder what "Shock Pads" are ?

David

[Grant Bowker]

This is a guess, maybe a bad one....
Possibly a reinforcing layer under the tread, either extra rubber or belts of cord (keeping in mind that most of the (high profile) tires of that era didn't need belts as part of their structure to remain in shape).

[Hanno Spoelstra]

This 1939 GoodYear Heavy Tractor tyre showed up recently in a lot of used tyres offered for sale by Bill Ruston

It has that peculiar pattern which I think makes the vehicle slip sideways in certain conditions. AFAIK this pattern was not continued in production later on during the war.

[Alex van de Wetering]

Originally Posted by Hanno Spoelstra

It has that peculiar pattern which I think makes the vehicle slip sideways in certain conditions. AFAIK this pattern was not continued in production later on during the war.

I remember seeing these in pictures of Morris CDSW tractors..... And I think also on fatcory pictures of 6x4 Leyland or Guy lorries..... But as you say very early war or even pre-war.
I think i have also seen them appear on a 25pdr used as a monument somewhere... But I can't remember where!

[David Dunlop]

That is a very peculiar pattern tyre, Hanno.

If it was possible to mount them on an axle in mirror image of each other, would that cancel out the tendency for the vehicle to side slip in the mud?

With the pitch of all four tyres pointed in the same direction, things could get very interesting on a muddy slope.


David

[Alex van de Wetering]

Originally Posted by Alex van de Wetering

I remember seeing these in pictures of Morris CDSW tractors..... And I think also on fatcory pictures of 6x4 Leyland or Guy lorries..... But as you say very early war or even pre-war.
I think i have also seen them appear on a 25pdr used as a monument somewhere... But I can't remember where!

Found them, Although I now see that the ones on the 6x4 3 Ton chassis are slightly different

@ David. Yes, you would think in mud you would be costantly turning the steering wheel in the opposite direction to counter the movement of the "drifting" vehicle (?).

[David Herbert]

The 3 ton 6x4 in the third photo is fitted with the first pattern of Dunlop Trak Grip tyres. These and the Goodyear and possibly other makes of "diagonal bar" style were very common at the start of WW2 and I suspect that they were a War Dept. design like the various 6x4 standard chassis. I have read somewhere (but have no idea where) that the Dunlop version changed to the later versions with the bars joined at the tyre centre line to reduce side slip in snow and ice and to promote longer tyre life. The more usual Dunlop Trak Grip went through quite a lot of detail changes over the years, particularly to where the tread bars merge into the sidewall. They saved rubber by having a depression in each one, then filled it in again and made the shoulders rounded. This would be a study in its own right.

Early Goodyear pneumatic tyres had a fine diamond tread pattern which became almost their trade mark. When they moved on to newer designs of road tyre they retained the single line of diamonds on the sidewall for many years so it is interesting that the "diagonal bar" Goodyears do not have those diamonds on the sidewall. Is it possible that the one in post #54 is a retread on a Goodyear casing though probably not as the Goodyear Sure Grip in post #44 also does not have diamonds on the sidewall though modern tractor tyres do. We need more examples of this style....

David

[Keith Brooker]

From a tyre manual i have, shows some tyres in use

Last photo of Germans with a tyre from a Guy truck. Photo from my collection

[Mike Kelly]

Wartime 900 13 tyres