18" tyres

[motto]

My suggestion of tyre designation 9.00-16.25 was based on the assumption that the HUP and the Humber 4x4 used the same wheel diameter as other WW2 British designed military vehicles with 16" wheels. These were about 1/4" larger in diameter than 16" American wheels.
Strangely enough the post war Ferret Scout Car used the smaller American wheel diameter. The run flat tyres for these were marked 'To fit 6.50 H Rims' if I remember correctly.
There are those who think the difference in wheel diameter is insignificant but I have tried putting tyres made for British rims on a Dodge WC and they were definitely a sloppy fit. Conversely, I know of at least one fellow that had his Blitz wheels machined to a smaller diameter to take American tyres. He was happy with the remaining thickness.

David

[Lynn Eades]

David, I am sure others know more than I, but as you have probably noticed, the majority of wartime 900 x 16 tyres had on them "for British wheels only" or "for 6"rims only" or " for American wheels only"
One wheel has a "flat" base, and the other, a "tapered" base.
Obviously the two allies couldn't agree on a common standard (like they did with the inch)
I had a Dodge 6x6 at one stage, and from the process of measuring up rolling circumferances of the 20 plus various 900 x 16s, I found few to be the same. As an example, the standard British Dunlop track grips were quite a bit smaller than the same make run flats. (The runflats were post war and should have been on a Ferret)
I also had British Avon, Michelin, Blackhawk chiefs, Yokohama (1960-70s)along with a mix of Goodyears, and other names forgotten, including sand tyres made in the Federal Republik of Suid Afrika. Obviously some were worn more than others, but as I recall the circumference varied a max of about 8 1/2". A lot in for 1 turn of the wheel!

[motto]

You're perfectly correct Lynn, tyres of the same nominal size from different makers can vary significantly in outside diameter. As you and Grant point out this also applies to different types of tyres (run flat, cross country etc) from the same maker.
However, it's the diameter of the hole in the middle that I was rambling on about. The topic that has been covered previously I know but there are those more recent victims of the OD bug that have yet to encounter this 16" wheel/tyre anomaly.
Bead angle aside, tyres made for wartime British 16" wheels are oversize enough to be quite loose on an American wheel as I proved again a couple of years ago when I inadvertently purchased the wrong ones.
I know that in the past some people have welded steel plates to the wheel bead area to centralise British tyres on Dodge WC wheels otherwise they could end up quite eccentric. I myself have in times gone by bonded rubber strips to the tyre bead for the same purpose.
Very little of this has to do with 18" tyres so once again I'm guilty of hijack. It just seems to happen in conversation.

Cheers

David

[Lynn Eades]

David, You are right to bring the subject up again. And yes, I digressed
On highjacking. Show me a thread that hasn't been.

[Matt Austin]

Some fascinating information here, thanks folks.

How would these go?

http://www.cokertire.com/1100-18-mil...dukw-tire.html

Cheers,
Matt

[jack neville]

See if you order them. There is a few US tyre sites that list them but they might not actually be available to buy.