Splitrims, punctures, & puncture repair (1 Viewer)

[lostmarbles]

I've been running splitrims for around 30 years.

The main reason for this thread is a "puncture-cause discovery" I made yesterday ... but I thought I'd expand it to include details on "DIY tyre changing" (relating to splitrims) because there doesn't seem to be much about this here on MUD.

(I'd be grateful if others who run splitrims can add their advice/experience to it too.)

So this all started with me experiencing a slow leak in my RH front tyre about a week ago. The pressure was dropping from my 35psi normal-pressure to about 10psi over a 4 day period.

1st step
Check the tyre for any tacks, nails, bits of glass etc sticking into it. ..... None in my case!

2nd step
Remove the offending wheel and remove the valve to allow all the air to escape easily:



(All my valve caps have heads for valve-removal.)

3rd step
Repeatedly run over it to break the bead from the rim.

Here you have to be BRUTAL and there is no point in mucking around with tyre-levers and hammers until you have the bead broken away COMPLETELY on BOTH sides.

I used the fence in my driveway to stop the wheel being pushed forwards each time my vehicle tried to mount it .... but if you're out in the sticks....a depression in the ground works just as well.)

 

[lostmarbles]

4th step
With the tyre bead BELOW the "ring", start levering the ring away from the rest of the wheel.

And work your way around until you have the entire ring off"

 

[lostmarbles]

5th step
Remove the tube:



Not forgetting to poke the valve stem inside:

 

[lostmarbles]

At this point you should be able to easily just lift the tyre of the rim.

But I'm interested in the cause of the leak .... so I simply blow the tube up and stick it in the sink in our laundry to look for bubbles.



Bubbles ahoy:



(If its a nice hot day and your kids are playing in the playpool in the yard... that's even better... Turf them out and stuff your tube in instead. )

 

[lostmarbles]

Now this brings me to the discovery (which was amazing to me) that forced me to start this thread.....

I'm ashamed to admit that some time back I accused another mud member (obviously more experienced than me) of exaggerating when they suggested a tiny paper sticker could cause a puncture in an inner tube.

Well .... crikey dick ..... here is the evidence that they were indeed correct...
(a closeup of the surface of the inner tube where the leak is):



Those diagonal lines are "impressions" caused by the "ribbing pattern" inside the tyre (and they haven't caused any wear on the tube that I can see). But the square sticker has indeed damaged the tube to the point where it is leaking!!!!!

And here is the remains of the offending sticker on the inside surface of the tyre:



I suspect the glue (behind the sticker) gripped the rubber of the unner tube and forced it to "crease" (perhaps especially during aired-down driving) leading to "fatigue-failure" of the rubber.

Any other opinions?

Here's a wider view inside the tyre showing the "ribbing pattern" inside a BFG all-terrain tyre (that some people claim can also be damaging to inner tubes ... )



(I'll add more later when I've got my new KM2 tyres I've just ordered)

 

[NMC_EXP]

Greetings

I worked in a tire shop 35 years ago. Serviced a lot of tube type tires on tractor/trailer rigs. These typically were 20 and 22 inch diameter "flat based" rims with removable lock rings.

I never saw a glued on tag wear a hole in a tube but it looks like that is what happened to you.

Standard procedure for servicing lock ring rims was:

1. Remove valve core to completely deflate the tire.

2. Make a witness mark on the sidewall of tire adjacent to valve stem location. This makes it easier to locate the object which punctured the tube.

3. With the tire/rim assembly on the floor, use a tire bead hammer (a.k.a. "duckbill" or "wedge" hammer) to break both beads loose from the wheel. I preferred the 18" handle model and rather than swinging it I hit the flat face with a short handled sledge hammer. This link shows the type of hammer:
Amazon.com: Ken-Tool 35429 Tire Bead Breaking Hammer: Automotive

4. Using a pair of tire irons gently pry the lock ring out of it's groove. Be careful not to spring, bend or otherwise distort the lock ring. A defective lock ring can kill you.

5. Remove the tube.

6. The tire should slide off of the wheel.

7. Locate the hole in the tube and patch it.

8. Using the witness mark on the tire locate the offending object in the tire and remove it. If the object roughened up the inside of the tire it's best to put a rubber boot (patch) on that as well.

9. Remove all dirt & debris from inside the tire. A grain of sand can wear a hole in a tube.

10. Install tube in tire and add just enough air to get the wrinkles out of it.

11. If a flap is used, install the flap over the tube.

12. Lightly lubricate both beads with soapy water. DO NOT use engine oil or any petroleum product as it will degrade the types of rubber used for tires. The lube allows the beads to slide out to the flange and lock ring at low pressure rather than popping out all at once at full pressure resulting in the need for a change of underwear.

13. Position tire next to rim and insert valve stem through the slot. Be sure the valve stem if pointed to the lock ring side. Lower tire onto the rim.

14. Start the lock ring so that the break in the lock ring is opposite the valve stem. This might aid in balance. If the lock ring is sprung, bent, cracked, etc, junk it and get a different one. Use a heavy rubber faced mallet along with a tire iron to work the ring into it's groove.

15. Lock rings can blow off during inflation for several reasons. They should be aired up in a safety cage or a heavy chain should be wrapped around the tire and through the rim center hole several times. A clamp on air chuck should be used so your hand stays on the end of your arm should the lock ring come off.

I have one concern with your procedure - that is driving on the sidewall to break the beads loose from the rim. This may damage the reinforcing cords and belts in the tire. This could ruin a tire. The tire bead hammer I mentioned is not cheap but it costs less than a tire.

Other info:

If you have radial tires, use tubes designed for radial tires. They can handle the sidewall flexing better than bias tubes.

Always keep valve caps in place. Without a cap dirt and grit gets into the stem around the valve core. When you add air this forces the grit down into the valve seat and you now have a slow leak.

Best regards,

Jim

 

[JohnnyC]

I use tyre plyers to break the bead...i had seen people do the tire way...and ...have never seen a tire get damaged....not to say that it couldnt happen

i have had the sticker cause damage...had it happen to myself.

we are running much lower pressures than semi's run the tube does 'move' inside the rim and debris could skuff and cause a leak...i make sure the inside is clear of any stickers as well as make sure the inside doesnt have any stray metal belt strands exposed on the inside...

i had found 2 bfg's with alil metal strand sticking about 1/32" out and made a nice lil hole and skuffed an area of about 1 1/2" diameter on the tube as well...when this happens i put a patch in that area and make sure i orientate the tire and rim the same as it was before.

i am running the same tubes (EDIT: just remebered one was newer...5? years ago) and flaps for the past 12? years...just with a few patches and new tires

i will be replacing my toyo m-55's with cooper st's soon and am kinda interested in the condition of the tubes...i'll see soon enough

 

[JohnnyC]

another repair thread i posted awhile ago...great info from 'BULL' here on Mud also:
https://forum.ih8mud.com/40-55-series-tech/319947-oem-split-rims-repair.html

 

[Slowerthanu]

Nice write up, I have been considering split rims for the simple fact that they are a rare item in the states.

Question, has anyone in this forum actually had a ring let go or known a person that it has happened to.

 

[lostmarbles]

Thanks Johnny, Jim, & Slowerthanthou.

I've obviously missed those "how-to threads" and should have searched first.

Anyway ... at least my photos of the "sticker phenomenon" will mean this thread has some use.

And perhaps I can make it even more useful by posting explanation photos to dispel the idea that these Toyota splitrims (in unmolested non-rustcompromised condition) can ever be lethal (or even cause injury) except to the severely intellectually disadvantaged (who may do any sort of unpredictable thing).

The steel-reinforced bead of the tyre actually prevents the "ring" from being able to expand at all. So there's no way in hell (under anything but EXCEPTIONALLY STUPID circumstances) that it can open up to the point where it lets go of the "ridge" at the top of the main part of the wheel.

Photos:








PS.

Anyone who starts inflating the tube (without a cage/chain restraint) with any of the tyre bead below the "ring" fits my description of "severely intellectually disadvantaged"

(I believe I don't need to use a cage/chain for protection because I never do that.)

Edit: Just checked my records. It took 5 years and 16,000kms of travel to get that sticker to damage the tube to the point where it began leaking. (August 2005 was the last time that wheel was apart.)

 

[FJforty]

If I were going on a safari or across the desert I would do split rims, they can be repaired almost indefinitely with hand tools. Nowadays good radial tires with a spare, plug kit, fix-a-flat, gorilla goop, and on-board air compressor is alot less work and worry. Well maybe...

 

[RED47]

I have just swapped over to full rims, I ran the BFG Muddies on the split rims for a while but was getting too many flats, there was a stage there when i was doing them quite regularly and managed to have the whole tyre pulled off the rim in 3 minutes!!
I liked the spit rims and muddies for the whole old skool look...but changed my mind when i had a rear tyre colapse a side wall on a main road going around a corner at about 80 KM/H!!
I was going to get a different brand tyre for the split rims but a mate of mine told me he could get 4 rims and tyres cheaper than he could get just the rubber for the splitties

 

[JohnnyC]

those are some great explanations 'lostmarbles' ...just to expand a bit further...here are differences with toyota rims over other style of split rims...

1st pic is Toyota Semidrop Center Rim with removable flange on the ring this is what makes it much safer than most other split rims...full bead applys pressure as it has a full flange base and deep lock

2nd pic is Flat Rim *unsafe style*

3rd pic is the Semidrop Center Rims (left one no flange base *unsafe style* and removable full base flange on right (semi-safe rim )

4th pic advanced flat rim *unsafe style*

5th pic is grader rim *unsafe style*

6th pic is earthmover rim *unsafe style*

 

[NMC_EXP]

Nice write up, I have been considering split rims for the simple fact that they are a rare item in the states.

Question, has anyone in this forum actually had a ring let go or known a person that it has happened to.

In my five years as a truck stop tire repairman I never had a lock ring blow off.

However, I did refuse to inflate several which had damaged lock rings or wheels.

The inflation safety cage in the shop was constructed from 3 inch diameter heavy steel tubing. Several of the tubes were bowed outwards a half inch or more from past blow offs. We were mostly working on 10.00 x 20 tires at 80 or 90 PSI.

Don't get me wrong - working on these is like a lot of other things, there is potential danger involved but it ain't Russian roullete. If you do it right and the rim and lock ring are in good shape it is not going to come apart.

What most folks refer to as "split rims" are actually multi-piece rims (solid flat based rim plus a split lock ring flange). The true split rim design consists of a solid lock ring mated to a rim which is split axially. These things were flat out scary to work on and probably caused most of the damage to the safety cage.

I suspect the now obsolete true "split rims" account for most of the bad reputation multi-piece rims have today.

Regards

Jim

 

[JohnnyC]

I suspect the now obsolete true "split rims" account for most of the bad reputation multi-piece rims have today.

Regards

Jim

I would agree with that...its a misnomer that ALL split rims are going to kill you....also...

truck rims as Jim would contest inflate to much higher pressures...seating the bead normally works at 40 psi...but if the ring is not seated fully or the ring is a damaged ring and you inflate to the full 105-120 psi that semi/trucker rims go then you can have a ring fly...and at that pressure ...they FLY.

 

[Slowerthanu]

Thanks for the responses and the pictures, it fully explains what these rims are. I have never really found an "unsafe" Toyota product.

 

[NMC_EXP]

I would agree with that...its a misnomer that ALL split rims are going to kill you....also...

truck rims as Jim would contest inflate to much higher pressures...seating the bead normally works at 40 psi...but if the ring is not seated fully or the ring is a damaged ring and you inflate to the full 105-120 psi that semi/trucker rims go then you can have a ring fly...and at that pressure ...they FLY.

Back in the 1970's most semi truck tires were bias ply. Radials and tubeless were just coming into use.

The 12 ply bias tires ran 80 to 90 PSI. The steel radials ran 100 to 120 PSI.

However, do not underestimate the amount of energy bottled up in a 7.50 x 16 at 40 PSI.

Regards

Jim

 

[JohnnyC]

However, do not underestimate the amount of energy bottled up in a 7.50 x 16 at 40 PSI.

NOPE

and thats why I do this ....because you just never know....my rings are very rusty

255/85r16 (33") tire

 

[NMC_EXP]

If I still had lock ring rims on my vehicles, I'd work on them myself and use a chain for inflation like you show.

As much as tire shops now charge for dismount & mount on a tubeless car tire, I'm thinking about buying a couple of tire spoons and doing that myself at home. Then take them to a tire shop for balancing if required.

Regards

Jim

 

[JohnnyC]

....Then take them to a tire shop for balancing if required.....

I worked my way around that also...i use Equal Tire Ballancer in my tubes...

the best part is when i get a flat...i patch it and the equal is still in the tube all ready to go

bad part is that equal to work correct to ballence requires speed over 35 mph to work efficiently...since i do quite a bit of highway ...it works well.