Heads Up: 10.50-16 directional tyres

[Geoff Winnington-Ball (RIP)]

Originally posted by Dirk Leegwater
Barry told me that the weather was very nice in Ontario
last week. To early back home for me ?

Only if you like bloody cold, damp and miserable, Dirk! Barry's observation is clearly one of the associated symptoms of his advancing C.R.A.F.T. Disease, poor lad.

[Mike Timoshyk]

Well,with all this talk of rubbers, not wellys or trojans, I thought that I would give a quick update as to my progress....DAMN!!! the old tires were difficult to remove, even from the split rims...but as you can see two are done and have been primed awaiting a final coat before mounting, no, not like a trophy whitetail or as some rum soden sailor in a back alley. So it is 2 down and two to go....don't have a spare rim yet...hint hint....

Cheers

Mike

[Hanno Spoelstra]

Originally posted by Mike Timoshyk
give a quick update as to my progress....DAMN!!! the old tires were difficult to remove, even from the split rims...but as you can see two are done and have been primed awaiting a final coat before mounting

Mike, take your time fitting them. As they fit snugly on Rob's HUP rims, I think you will have a hard(er) time fitting them to your 15-cwt wheels, as they are larger in diameter. Would love to hear if and how you get them fitted to your rims.

Cheers,
Hanno

[Mike Timoshyk]

Thanks for the advice Hanno, yes I will be careful. As you can see I didn't run out and get them mounted the very next day....slowly but surely....gotta take time out for some grapes.

cheers

[Hanno Spoelstra]

Originally posted by Mike Timoshyk
Thanks for the advice Hanno, yes I will be careful.

Mike, while sipping on your wine make sure to read Richard Notton's experience fitting Simex ST24 Trak Grip tyres to CMP rims back in May 1999. Eight years later we have learned it is not the bead angle, but the larger rim diameter which makes fitting US tires to British rims difficult, but the process he describes should give you an idea of what you could be about to undertake:

I've posted this info piecemeal to interested individuals previously but
this is just the forum now to spread it further, it wont be short,
please bear with me.

(...)

British v Canadian rims and fitting.
Its a bit incredible that we went to war with two identically defined
tyre sizes that are actually different, all is not lost. The difference
as far as I can determine is the tyre bead angle, everything except the
Canadian is a 5º bead (to the horizontal or axle line), the Canadian
tyres are 0º, theoretically this makes the Brit ones easier to get off
as they become sloppy on the rims with the smallest movement away from
the rim edge.

We have heard the tales of rim machining to ease the current types onto
Canadian rims and people shaving off the inner lip of the bead with a
utility knife, but its not really needed, the bead on modern tyres seems
to be quite flexible enough to fit but it is a struggle. Here's how we
have done it several times over on a F15 with various current
manufacture 9.00x16's, let me stress its our way and I am not advocating
or recommending the method which has its dangers if extreme care is not
taken as I hope will be patently obvious.

Once on, the 5º bead angle tyres WILL need a hydraulic truck sized, four
arm bead pusher-offer of substantial grunt to remove them again, you
will never get them off at home.

You need an extra pair of understanding, strong, competent hands, don't
for one moment think wife/girlfriend/lad next door can lend a hand when
needed.

Clean, shot-blasted, painted rims are an essential starting point, just
getting the tube and flap in a new tyre is difficult, the beads are
always sprung together, whichever way you seem to fit these the flap
hole, valve, or both, always seem to be pointing the wrong way no matter
how hard you try to deduce where they are going to end up, the flap
often gets slightly too far round and needs taking out to stop it
pulling the valve sideways.

You need a lot of rubber lubricant - washing-up liquid contains salt and
will rust the rim, Vaseline/petroleum jelly rots rubber, we have used
Hellerine - a commercial rubber lubricant used in the electronic
industry for fitting rubber sleeves on wiring, its made by Hellerman;
this stuff is thicker than 90EP and twice as slippery. You will find a
air impact wrench almost vital for spinning the split rim nuts on and
off unless you happen to be Mr Universe. You will get very hot, very
angry and totally filthy.

Get the tube in and give it a little air, valve core removed, to open
the beads and see where the valve settles, get plenty of lube up the
inside of the bead for at least an inch, struggle with the flap and get
it all in then add a puff of air again and see all is sensibly lined up,
it probably wont be too well.

Really, really lube the bead; really lube the whole of both the inner
rim faces that form the well right out to and up the rim edge. Lots.

Put a long brass extention on the valve, it will disappear if you don't,
place the tyre on the inside rim as square as possible, it will only
just sit on it, put the outside rim on and start the two long rim studs,
pull them down enough to start all the rim nuts by nearly half depth.
Don't over-do it you WILL pinch the flap and tube somewhere.

Put a _little_ puff of air in, just enough to make the tube take shape,
and with a mirror and a bit of flat wood inspect between the rims and
encourage the flap, by pushing with the wood, to centralise itself and
go up into the tyre a bit, but don't over-do it as the flap will pop out
elsewhere.

This bit is POTENTIALLY LETHAL and intrinsically UNSAFE - BE WARNED.

Ensure you're happy that the two long studs have a sensible amount of
thread engaged and all the rest have at least two or three turns on
them, all should be just bearing on their seats. With the valve core
still out to allow instant deflation, GINGERLY, inflate in short bursts
until you see the beads start to move up and out along the rim, it takes
a moment, give it time and NO MORE THAN 10 -15 psi, as soon as this
happens remove the inflator immediately.

The rims will likely now fall together when it deflates which is a good
sign, to be certain, lever them apart and inspect with the mirror to see
the flap is now properly up in the tyre and will not get trapped
anywhere. Torque the split rim nuts down fully and inflate, the beads
will pop out fully onto the rim edges at about 20 - 25 psi, remove the
extention piece and fit the core, bring the tyre up to about 50 psi and
check the side wall concentricity rings, a few hearty thumps with a
hide-faced mallet usually corrects any slight anomalies.

If you can't immediately visualise what I've described and how to
achieve it, then I make the only recommendation herein, which is that
you should NOT be doing this at all.

Richard
(Southampton UK)

Source: http://groups.yahoo.com/group/CMP/message/70 (yes, I'm a search guru )

[Mike Timoshyk]

Once again Hanno THANKs....I have wrestled a few split rims before on 18 wheelers.....no easy task and always very risky. We would inflate the buggers in a cage....just in case. Yes most important in several situations is LUBRICATION. I will not go into the others, however with setting beads yes....more is always better. I will probably wrestle with the first one and if I get too frustrated I will, as usual, follow my wife's advise and go to a shop and get it done. NO she does not follow MLU and I am not quite as below...

[Tony Smith]

Originally posted by Bob Carriere
And of course by law they must contain all the stupid warning molded into the side walls...like do not inflate to 2000 pounds .... do not put them in your nose.... keep away from children.

That's probably why they only come in 10.50-16, there wasn't enoguh room on the sidewall of a 9.00-16!

Coker last made their 10.50-16 within the last 5 to 10 years. They too were made for them by Specialty Tires of America, so I would expect they would have the modern construction features on the inside.

Originally posted by Bob Carriere
And of course by law they must contain all the stupid warnings...do not put them in your nose....but they smell so goooood!!!! fresh rubber.

Bob, if your rubber fetish prevents you from heeding warnings about putting them up your nose, I think you might have a problem.
"But Officer, I have "COKER" on speed dial to help deal with my addiction. They're my favourite dealer!"

[Tony Smith]

Originally posted by Hanno Spoelstra
Mike, take your time fitting them. As they fit snugly on Rob's HUP rims, I think you will have a hard(er) time fitting them to your 15-cwt wheels, as they are larger in diameter.

True, as I have a couple of new 9.25-16 tyres that were originally for a C8A or Lynx and they won't fit on an F15A rim.

The 8 stud 16" rims are what are called "British Rims" while the 6 stud 16" rims on C8A HUPs, C8AX and Lynx are to the slightly smaller "American" dimensions.

[Bob Carriere]

Mr. Clarke....... front and center....

"your next assignment is to show that the %&&$#@% tire will fit on a Canadian Military Pattern wheel...."

Mr. Bowker....... get us a large can of elbow grease... the Canadian pure lard kind.....


.....and I will man the camera....record the event...!!

...........sh** someone has to supervise!!!!

BooB

[Bob Carriere]

Tony

From what you say the Hamawrickans have a different unit of measure......

We all know the US gallon is short by 20%......

...but I never realized that they were short an inch on 16.....

We will carefully measure the HUP substandard size wheels with a Hammond caliper and compare to a full size well endowed CMP wheel to see if we can find a noticable differences.......I do know the nuts are all the same!!!

Maybe we should measure it in French..... and risk getting all our Aussie friends aroused!!!!

BooB

[Geoff Winnington-Ball (RIP)]

Oh brother, why does it always come back to that??!! Yer gettin' me goin' ag'in, Boobie! Jeez.... must be somethin' in the air up there.... or mebbe yer spendin' too much time down at Chez Cheri....

[RHClarke]

Originally posted by Bob Carriere
We will carefully measure the HUP substandard size wheels with a Hammond caliper and compare to a full size well endowed CMP wheel to see if we can find a noticable differences.......I do know the nuts are all the same!!!

It's not the size of the rim, it's how you use it, dammit! Substandard rims indeed...You have rim envy.

If you feel up to it, Bob, just mosey out to my shelter and in the back you will find two HUP rims. There is a "substantial" eight bolt rim in the shed, and I am sure a few split rims of the same massive dimensions in the shop.

A photo of both rims lined up rim to rim should give you your answer.

[Snowtractor]

Originally posted by RHClarke
A photo of both rims lined up rim to rim should give you your answer.

You guys probably missed in, but sometime in the early 19th century they invented this thing called the "TAPE MEASURE". Hard to find , granted, but one of them might work.
Sean

[Geoff Winnington-Ball (RIP)]

Pssst, Sean.... don't forget, this is the Ottawa Valley we're talking about here...

[RHClarke]

Originally posted by Snowtractor
You guys probably missed in, but sometime in the early 19th century they invented this thing called the "TAPE MEASURE". Hard to find , granted, but one of them might work.

Ok. Found one. Now what? Maybe some help from the Toronto area might solve this one...

While I am sure that the impact of sending measurements of items thrills the average westerner, we in the east (OK central area - less Toronto) prefer the visual impact.

E.g.:

western approach: 36, 24, 36

our yokel approach: ....... oops....

See the difference? Which do you prefer? Thought so. Photos of rims to follow...

sorry mate, but their program can trace the link referral back here for spamming purposes if they are that ilk...

[Snowtractor]

Originally posted by Geoff Winnington-Ball
Pssst, Sean.... don't forget, this is the Ottawa Valley we're talking about here...

Ah, 14th century, gotcha. Hmmm, didn't they invent "the stick" about then. Alright, we'll go with that...okay listen carefully boys:

Get stick (preferably straight... no no no, I meant dimensionally straight!!!!) { this is going to be harder than I thought}

lay stick across first wheel , gnaw mark on stick ( get young'in to do this , as you fellas ain't got no teeth )

take stick and lay across other wheel ( lay the stick , fellas , not yourself) { for pete sake its like training a monkey...and a slow monkey at that }

Sorry for the aside gents, I was just saying you're special people


now, is the mark on the stick resting in the same place on the second wheel as it did on the first wheel?

there you go ....

you can buy the book on tape version of "Stick Measuring in 17 easy steps" and have someone read it to you, just send me your credit card numbers asap.



Sean

[RHClarke]

Originally posted by Snowtractor
Get stick ...(blah, blah, blah)... now, is the mark on the stick resting in the same place on the second wheel as it did on the first wheel?

Sean,

OK, So, what did your "stick" say? What's the difference between the rims? You couldn't have gone thru all that without actually doing it, right?

[RHClarke]

Originally posted by RHClarke
Ok. Found one. Now what? Maybe some help from the Toronto area might solve this one...

While I am sure that the impact of sending measurements of items thrills the average westerner, we in the east (OK central area - less Toronto) prefer the visual impact.

E.g.:

western approach: 36, 24, 36

our yokel approach: ....... oops....

See the difference? Which do you prefer? Thought so. Photos of rims to follow...

sorry mate, but their program can trace the link referral back here for spamming purposes if they are that ilk...

Geoff,
That kinda blows the snot out of my theory if the visuals don't show, so, please link to Tony Smiths "lady" found in the Red and White Nuts thread in the Sergeant's mess (can't do it from work as the Puritans are lurking...). Thanks

[Geoff Winnington-Ball (RIP)]

Originally posted by RHClarke
Geoff,
That kinda blows the snot out of my theory if the visuals don't show, so, please link to Tony Smiths "lady" found in the Red and White Nuts thread in the Sergeant's mess (can't do it from work as the Puritans are lurking...). Thanks

Rob, sorry, should have explained better... the visimods DIDN'T show, it's that anyone going there from here would automatically leave MLU as the Referring Agent in their logs, thus inviting them (or related interests with access) to say "Aha! Another potential customer to spam!", and come running over to drum up business. I spend enough time dealing with the spammers and troublemakers as it is...

No worries, not your fault - you have to know how these things work from the inside.

On the related note, I'll have to go fishing for the pic you're referring to...

[Geoff Winnington-Ball (RIP)]

Originally posted by Geoff Winnington-Ball
On the related note, I'll have to go fishing for the pic you're referring to...

Just found it.... good god, I can't go into THAT one here! I'd be out on the street in no time flat...

Incidently, nice thread! Funny as hell... and good old Art Johnson right in there with the rest of us...

RIP, Art!

[Mike Timoshyk]

got "it" mounted...got dirty and now it won't fit on the truck???

Did it get BIGGER?

[Geoff Winnington-Ball (RIP)]

Just push the truck out into the rain (sprinkle on a little fertiliser first)... it'll grow to fit the tyre.

[Bob Carriere]

How did you get your new tires soooooo dirty...??

I why would they not fit....??? did you rub them with Viagra????

Who is the little munchkin...... you know child labour is gainst the law..... or did you promise him the truc would be his when he grows up????

BooB

[terry johns]

Fellow CMP Owners,

If you have not ordered your new set of 10.50-16 tires, might I suggest holding off until the results are in.

I received four of the new 10.50-16 tires everyone is talking about.

I had a spare wheel for my 1941 C30 all sandblasted and painted awaiting some new rubber to install.

I dropped this wheel and a new Specialty 10.50-16 Chevron tire off at a large truck tire dealership which has mounted many of my WWII combat type rims previously. When I returned to pick it up I was told that they could not fit the tire onto my (Kelsey made in Canada) wheel because the tire bead was too small.

I attach a photo of the wheel so there can be no misunderstandings about what wheel I have.

Not one to be easily put off I had them dismount another old WWII tire so I could sandblast, measure and try anew with a second wheel.

Here attached, are the dimensions that an engineer and myself took yesterday from a Kelsey 16 inch wheel from my C30 and a post-war Jeep 16 inch US wheel.

Also of note: we measured a modern US 16 inch pick-up truck wheel and it too was the same dimension as the much earlier Jeep wheel.

I believe these tires are 1/8 - 3/16 inch too small to fit our 16 Inch C30 & C15 WWII CMP wheels.

I'll bet they will fit US GI WC, M37s and modern US 16 inch pick-up wheels just fine.

Cutting and trimming the tire's rubber does not sound like a smart idea to me.

Machining .125 - .185" off a wheel's metal might not be a bright idea either but I would be more inclined to do this than cutting on the tire. The Kelsey wheel is made from steel that is .320" thick. To remove .185" (3/16) from the rim's root outside diameter would require the removal of .0925 (per side) from the thickness of the wheel's steel leaving the metal approximately .230" thick in the center. If you could get by with removing only .125" or .0625" per side, we would still be reducing our potential strength of the wheel by about 40% (at this point). Unless you have access to a very large lathe or cylindrical grinder, I am certain this would not be an inexpensive endeavor. If you did opt to machine your wheels to fit the tire what happens if at some as yet unknown time in the future, some one offers us a correct tire at the correct bead size?

I previously owned a C15 and found five original NOS 10.50-16 tires at a warehouse in St. Louis. (No there are no more...I bought the only five they had.) I had these tires mounted by the same tire dealership mentioned earlier. They fitted with no problem what so ever. One tire was a Dunlop, one a Firestone, one a US type bar grip and three were Goodyear Sand treads. And I too thought the bigger tires looked better than the smaller 900s. I also found my 216 powered C15 would go a full 4 mph faster with the bigger tires. I know that is not much but every little bit helps.

Presently I have two Czech Mitas IM-10 tires that I got from a wholesaler in South Carolina. I became of these tires when I saw the Bofors AA Lorry on display at the Firepower Artillery Museum in Woolwich, England. But I have been unable to acquire a further two tires from this source but have found a UK dealer who is willing to get them. I think I'll go with two more of those Czech Mitas IM-01 tires. At least they fit properly and have given me no problems.

Terry Johns
St. Louis, MO
1941 C30.


P.S.: Here is that pic of my freshly blasted Kelsey wheel

[Phil Waterman]

Originally posted by terry johns
If you have not ordered your new set of 10.50-16 tires, might I suggest holding off until the results are in.

Hi Terry

You raise a good point, I'd like to offer a little clarification I have 16" rims on my HUP which are 6 lug rims these take the standard US military tires without difficulty, no trimming. I also own a C60L with 16" rims which are 8 lug rims which will not take the tires that fit on the HUP rims. To get the US tires to fit the 8 lug rims it requires trimming a small amount of rubber (no cording or fabric) off the outside edge of the bead (the first bit to hit the rim when mounting). Your point about not cutting the metal or trimming the rubber is of course good advice particularly if it can not be done uniformly.

To trim the 900x16 US NDs on my 16 inch 8 lug rims, I mounted the tires on a large Lazy-Susan so that they could be rotated while a air grinder with a fine sanding disk can be used to reshape the tires rim lip so that it would slip on to the rim. In my case only a very small amount of rubber had to be removed to get all four tires to mount correctly.

I have also noted that there is often a mounting problem if the tires have been sitting in a stack and the two beads are squeezed together which changes the angle of the bead as it first contacts the rim. Spreading the beads rolls them apart which changes the angle at which they first engage the rim. In attached photo you can see how I mounted brand new 11:00x20s on the C60 twenty inch rims this particular tire had been at the bottom of the stack and would not go on easily, with tube slightly inflated and lowering the tire square to the rim it went on with out difficulty.

Now just to add to the confusion the 20" 8 lug rims take the US tires with no trimming problems.

[terry johns]

Here are those 10.50-16 dimensions mentioned earlier.


Additional...I too had no problem when I mounted US 900-20 tires on my 1942 British built Humber MKIV armored car's 20 inch wheels.

TJ

[Hanno Spoelstra]

Originally posted by terry johns
When I returned to pick it up I was told that they could not fit the tire onto my (Kelsey made in Canada) wheel because the tire bead was too small.

(...)

I believe these tires are 1/8 - 3/16 inch too small to fit our 16 Inch C30 & C15 WWII CMP wheels.

That concurs with Mike Kelly's measurements in the thread 9.00 X 16 U.S. versus British wheels. For me it puts an end to the debate on why these tyres & rims don't mix & match: it isn't so much a case of the 0° versus 5° degree bead angles, but the considerable difference in bead diameter. Period.

Somehow only the 8-lug 16" wheels are different in size, the 6-lug 16" and 20" wheels have the same size as American ones.

Hanno

[Hanno Spoelstra]

Originally posted by terry johns
what happens if at some as yet unknown time in the future, some one offers us a correct tire at the correct bead size?

Currently I know of only one tyre manufacturer who is offering 9.00-16 tyres in both sizes: one for American, one for British wheels. See new 9.00-16 tyres for WD split rim wheels.

HTH,
Hanno

[hrpearce]

All this is why I took the easy way out and fitted 31x10.50R16.5'sto my blitz. They don't look the part but considering the work I do the old girl will climb a cliff with these fitted.

[terry johns]

Here is the dimensions we took first of my freshly blasted Kelsey wheel from my 41 C30.

Here is why we've been having trouble fittings US tires onto you eight hole CMP 16 inch wheels. The wheel actually measure over 16 inches!

Mike's drawing indirectly refers to this problem.

Notice that the US post-war Jeep's wheels measure under 16 inches. Even my friend's modern pick-up truck 16 inch wheel measured the same as the Jeep wheel.

I called another friend who has a set of new Wallace Wade 900-16 US ND type tires for his WWII WC Dodge sitting in his garage. I asked him to measure the inside diameter over the phone. You guessed it...15 3/4 inches across the bead, the exact measurement we got with Wade's new 10.50-16s!

Gentlemen, I conclude these tires are made to fit US wheels and apparently ( I sumize) will fit the six hole CMP wheel (see the green wheel shown earlier) but not the eight hole 15 CWT or 30 CWT wheel.

To the man from Austtralia...My former C15 arrived from Canada with a set of 16.5 inch tires on the rear.