History of 10.50-16 tyres

[mlombard]

Hi

Ok so I know that the subject of CMP / Blitz tyres has been done to death here, and I'm not about to repeat it, BUT I'd like to know the history of some military tyre sizes. So we have:
9.00 x 13
9.00 x 16
10.50 x 16
11.00 x 20
My particular interest is 10.50 x 16, the reason is I was chasing some, like many others.

However I am lucky enough to have access to quite a heap of old tyre catalogues and some Tyre and Rim Association publications. So, and this is where it gets interesting, these catalogues have lots of tyre types and tyre sizes, and they go back to the early 1950's at least.

So I can find all the others sizes in these catalogues, 9.00x13, 9.00x16 and 11.00x20's etc., but nothing, nada, zilch about 10.50x16, they have 10.00x15 and 10.00x20 etc. But,, and here is the really interesting thing, it has 10.50x16 when it comes to inflation pressures etc., and tells me the ply rating etc. So whilst the tyre companies, and we are talking Dunlop, Goodyear and Perdiau etc. here, acknowledge that they exist,, they didn't sell them, well not at least to a civilian market, post WWII. So anybody care to shed some light on this.

[Bob Carriere]

There was also a 9.25x16 lower profile used on HUPs and a 10.50x20...... and other odd period specific tyre size such as for the 18 in. rims.

I would love to get my hands on some new sand tires used in the forties BUT they are no longer made in 16 in. format
except for agricultural use and usually at 16.1 or 16.5 and cannot be used on a licensed road vehicle.

It is possible that the reference books you have are not old enough.......... it is possible that by the early 1950s they were no longer made/listed/sold because there was no demands and lots of surplus military stock.

The only reason 10.50x16 are discussed so much is that someone took the time to reproduce the old size in a modern casing and get them MOT approve for road use.

Simple supply and demand...... we no longer can find 9:00x13 because very few people world wide needs them or the elusive low profile 9:25x16......

There was some rumour that the limited collectors market for the Specialty 10:50 was now in very short supply due to diminishing demand..... some form of market saturation..... and that the current demand was not sufficient to justify running another minimum batch of 2 or 3 hundred.

A few collectors are getting there hands on the remaining 10:50x16 currently in the supply network and storing them for future projects. I am sure a new batch will get manufactured as soon as the demand/enquiries/orders start pilling up BUT when?????

Cheers

[Keith Webb]

20" were generally 10.50 not 11.00.

[Tim Bell]

10.50 x 16 tyres - seen on many UK based Bedford OYDs and the like.

http://www.mitas-tyres.com/gb/product/1013308610000/

Hope this helps

Tim

[mlombard]

Hi

Thanks for the info, about finding the actual tyres. However I'm still interested in the history of some of these sizes, when did they come in i.e you see the size only listed from 194? onwards, and when did they go out (if they did).

I heard years ago that the US military wanted a specific unique tyre size for the Hummer and one of the reasons was to make it unattractive to those with light fingers as it wouldn't fit anything else, I believe that only lasted a short time before other vehicle manufacturers also used the same tyre size, true or not it would make sense, at least in the short term.

Re 9.00-13 Sand Grip Tyres that are or were a Bridgestone product. So again when and where did this 9.00-13 size come from. What lead the British /Canadians to adopt this size tyre, was it a high flotation tyre used on agricultural impliments before the war?, I've seen photos of Bagnold running around the Libyan desert pre WWII in old Ford Model A's with ballon tyres , but they were not 9.00-13's, from memory.

Its all interesting history.

[gjamo]

Some knackered 9.00x13 sand tyres on Gumtree at the moment.

http://www.gumtree.com.au/s-ad/toowo...es-/1115463264

[Mike K]

I recall reading that the 9.00-16 military tyre was a W.D. and Dunlop co-development during the 1930's. The early 15cwt rims were not the split type , they had a locking ring with four lugs .

Found this pic of a CS8 prototype ? maybe circa 1934/35 . The tyres look to be 9.00-16

[cliff]

easy to see where the CMP got it's looks from

[mlombard]

Originally Posted by Mike Kelly

I recall reading that the 9.00-16 military tyre was a W.D. and Dunlop co-development during the 1930's. The early 15cwt rims were not the split type , they had a locking ring with four lugs .

Found this pic of a CS8 prototype ? maybe circa 1934/35 . The tyres look to be 9.00-16

So it looks like the tyre and the truck (CS8) were developed together, and the rim system came along a bit later, possibly in a response to the issues of changing a lock ring tyre in the field, so to speak. It all makes sense.

[Andrew H.]

Originally Posted by mlombard

I've seen photos of Bagnold running around the Libyan desert pre WWII in old Ford Model A's with ballon tyres , but they were not 9.00-13's, from memory.
Its all interesting history.

See attached photos for Model A balloon tyres in the Egyptian desert in the early 1930s (Some are Bagnold and some Arkwright).

[mlombard]

Originally Posted by Andrew H.

See attached photos for Model A balloon tyres in the Egyptian desert in the early 1930s (Some are Bagnold and some Awkwright).

Oh ok, maybe I was wrong these look like or pretty similar to a 9.00x13 tyre, wish I could blow the pictures up enough to read the sidewalls.

[mlombard]

Originally Posted by mlombard

So it looks like the tyre and the truck (CS8) were developed together, and the rim system came along a bit later, possibly in a response to the issues of changing a lock ring tyre in the field, so to speak. It all makes sense.

Ok so I guess that begs the next obvious question where did the split rim come from, not the one with the locking ring, but the true split in half type rim like on the CMP. Was it a unique development for the military, or an adaption from a civilian use i.e earthmoving or something similar

[mlombard]

Originally Posted by Andrew H.

See attached photos for Model A balloon tyres in the Egyptian desert in the early 1930s (Some are Bagnold and some Awkwright).

hi Andrew the lower photo, was of the type I'd seen on other Bagnold photos, the first three I had not seen before

[Mike K]

Another possible user of 9.00-13 tyres would have been the oil exploration teams , these guys pre WW2 , explored what is now present day Iran and Iraq , roaming across the desert .

[Andrew H.]

Originally Posted by mlombard

hi Andrew the lower photo, was of the type I'd seen on other Bagnold photos, the first three I had not seen before

Yes, the first photos (with fatter tyres) are of the British army (ie the Sudan Defence Force) expedition Model A Fords, under Captain Arkwright in the early 1930s and the last photo (with slightly less-fat tyres) are of Bagnold's Model A's. As fat tyres were adopted for desert use by Arkwright and Bagnold in the early 1930s they were probably the forerunner of the 10.5 X 16 tyres later developed for British army CMP trucks in the desert. I do not know the dimensions of the balloon Model A tyres in the photos, but for what its worth, standard Model A wheel rims from the factory had an outer diameter of 21 inches (1928-29 cars) and 19-inches (1930-31 cars) and Model AA trucks were probably larger.

[Phil Waterman]

Hi Guys

Took me awhile to find it but here is a link to older thread post with Prewar Fords with balloon tires.

http://www.mapleleafup.net/forums/sh...2&postcount=12

Cheers Phil

[cliff]

have deleted unnecessary posts for you guys

[Tony Smith]

Also, the Wartime 10.50-20 tyres were replaced post-war with 11.00-20, but it seems to be just a name change as dimensions and ratings remained the same.

And 9.00-16 and 9.26-16 tyres have identical carcass dimensions, but the 9.00 size is for "British" rims, while the 9.25 is for the tapered seat rim used on the C8A and Lynx, aka "American" rim.

[lynx42]

Originally Posted by Tony Smith

Also, the Wartime 10.50-20 tyres were replaced post-war with 11.00-20, but it seems to be just a name change as dimensions and ratings remained the same.

And 9.00-16 and 9.26-16 tyres have identical carcass dimensions, but the 9.00 size is for "British" rims, while the 9.25 is for the tapered seat rim used on the C8A and Lynx, aka "American" rim.

Tony, Not to sure you are right to say the carcass dimensions are identical. The Lynx 9:25 tyres are a low profile tyre and are many inches smaller in diameter than the 9:00 tyre. I have been told that the extra:25 is actually the width difference of the tread.

Here is a photo of my new 9:00x16 tyres next to a slightly worn 9:25x16 tyre off my Lynx. You can see the 9:00 is taller and also narrower than the 9:25 tyre.



The new 9:00x16 tyres did drop onto the Lynx rims very easily.

Regards Rick.

[Tony Smith]

Originally Posted by lynx42

Here is a photo of my new 9:00x16 tyres next to a slightly worn 9:25x16 tyre off my Lynx. You can see the 9:00 is taller and also narrower than the 9:25 tyre.
The new 9:00x16 tyres did drop onto the Lynx rims very easily.

Regards Rick.

It's not equivalent to compare modern production tyres with wartime production. By far, the bulk of modern 9.00-16 tyres are made to different cross section shapes to WW2 tyres, and virtually all are of the "American" or 5 degree bead seat design.

I do have 2 WW2 Canadian 9.25 tyres and the carcass size is the same as Canadian and English 9.00-16 tyres I have. However, both 9.25s are from different manufacturers and while the tyre widths are the same, the tread widths are different

I also have two near-new Australian made 7.50-16 bar tread tyres (from Land Rovers) which are over an inch in difference in diameter. The point I am trying to make is that tyre sizes are indicative or nominal, and are intended to provide more information than simply the physical dimensions.

[Tony Smith]

Also, the 9.25-16 sizing seems to only be a uniquely Canadian idea. English-made tyres (WW2 production) for 5 degree bead seat are designated "9.00-16 for American Wheels".

[Mike K]

I believe the 9-25 X 16 was also used on British Humbers , the 4X4 FFW PU and the Box ?

I tend to agree with Rick, the 9-25's had a lower profile ( nothing to do with brands ) and this low profile was a deliberate design spec. .

[mlombard]

Hi

This is interesting considering we were all feed the line over the years that the Allies won because they standardised everything and the Axis lost because they could stop inventing and re-inventing things. And yet here we are with two tyres which on the surface would seem too close to one another i.e 9.00 and 9.25 to bother with, yet they did it and produced both. Can't imagine in the heat of battle and looking for a spare tyre I'd have been too choosie!, not like I'm going to be stopped for a roadworthy as I'm rushing forward from El Amein or worst back from Tobruk!!

[Hanno Spoelstra]

Originally Posted by Tony Smith

Also, the Wartime 10.50-20 tyres were replaced post-war with 11.00-20, but it seems to be just a name change as dimensions and ratings remained the same.

As posted before, this actually was a wartime change - see the bold quote:

Originally Posted by Hanno Spoelstra

Indeed. I have even seen a tyre sidewall marked "11.00-20 replaces 10.50-20". I have since learned this was a "new alternative size marking" for the 10.50-20 tyres listed in the wartime Data Book of Wheeled Vehicles, so it must have been a wartime change.

Interestingly, while this tyre originally had Dunlop TrakGrip tread, it was recapped at least twice, the last time with NDCC bar tread.

[Richard Farrant]

Originally Posted by Mike Kelly

I believe the 9-25 X 16 was also used on British Humbers , the 4X4 FFW PU and the Box ?

I tend to agree with Rick, the 9-25's had a lower profile ( nothing to do with brands ) and this low profile was a deliberate design spec. .

Hi Mike,
Quite correct, and the Humber Scout Car was also on Runflat 9.25-16 tyres. I have driven a Humber Scout on 9.00-16 and it is considerably more high geared due to the increased circumference. Especially awkward when trying to get it up on the neck of a low loader semi-trailer.

[mlombard]

Hi

So what was the reason for 9.25 x 16 versus 9.00 x 16 surely when they were trying to keep rubber use to a minimum one tyre would have been easier to produce, Was it something to do with weight carrying capacity, they were both off road tyres right, so there would have been no need for different performance characteristics surely. Was it something to do with the 'run flat' requirement on armoured cars etc.

regards

Matt

[lynx42]

It is amazing what turns up sometimes. This is a copy of a photo in an article in the latest Classic Military Vehicle magazine about the Morris Light Reconnaissance car.

It is the contract card for an order for Mark 1 cars and shows the tyre size required. - Tyres. 9.25-16R.F.



So here we have another vehicle which used the 9.25 x 16 tyre.

Regards Rick.

[mlombard]

Hi Rick

Still begs the question Why, what was so different in the technical specs between a 9.00 and 9.25 tyre.

Matt

[gazzaw]

Whilst whetting me appetite on the tyre history does any of you knowledgeable people have any idea or intel on a source for 10.5 x 16s as will be needing a set soon

Regards

Gary

[Bob Carriere]

The size you are looking for are available this side of the pond, as modern 8 ply ratings with the tractor thread made by Specialty Tires of America. They are distributed by Universal tires and Lucas and currently around $340 US $$$
In the last 10 years the cost has gone form the initial $199.99 US to the current price....... do not wait for them to go on sale!!!!

Note: Wallace Wade Tires of Texas, 10:50 tire distributor, has now closed....no reason available.

On the issue of size.....We have accumulated various old tire casings over the years some are original, heavy as hell, run flat casing dated 1940.

Why the different size????. when you stand up the various tires the 9.25 x 16 found on a HUP is the shortest of all..... sort of a low profile.....followed by the regular 9.00x 16 and tallest the 10.50 x16.... which is a few inches shorter than the 11.00 x 20.

We have all read the importance of matching the circumference of tires on a 4x4 but it is unbelievable the differences height we have observed between 9.00 x16 of the 70s to 90s era Dodge tires...... as much as 2 inches difference in height when mounted and fully inflated between known brands such as..... Firestone, Goodyear, Mohawk, General, etc. are all slightly different........ and if extremes are mixed.... big time binding of the power train.

Some one from the UK must know some distributor channels!!!!

Good Luck

Cheers