New tyres on road roller

[fred]

What tool is he using @ 28:30 to help mount the tyre on the rim

[Colin Bignell]

To judge from the rest of the video, it is probably not the right one for the job :-)

[NY]

After several attempts with the strange yellow air compressor, the flammable liquid and the *flamethrower* (WTF!), he finally manages to ignite the liquid to compress the tyre at 30:20. Would I trust a tyre that has had a flamethrower played all over its walls? Would I f**k! I bet the workshop stank of molten rubber.

[Andy Burns]

looks like it's "just" an airtank with a GBFO nozzle on it

[John Rumm]

That is kind of his MO all over - but he usually gets the job done... the entertainment usually being just how sketchy it looks on the way there!

[Harry Bloomfield Esq]

The yellow tank is an air tank, adapted to release a rapid enough flow of air, to blow the tyre onto the rim - which failed to work. The alternative method, which worked, was to fill the tyre with propane or butane, then set fire to it. The pressure of the explosion of the lit gas, worked in the end.

[NY]

Does the design of a tubeless tyre make the tyre bead naturally press very firmly on the rim of the wheel, even when the tyre is deflated by a puncture? Otherwise, how can a tyre pump inflate a flat tyre without the air leaking out of the bead/rim joint faster than the pump can deliver it?

On a car wheel, when the tyre is removed to repair a puncture and is then replaced, does the bead immediately make a gas-tight seal, or is it necessary to blast air in at a greater rate than the initial loss through the bead, until the pressure makes the seal gas-tight? I've never noticed tyre repair garages having to blast air in at a greater rate than you'd get with a normal pump, so I'm guessing that the bead is designed to seal.

[Tim+]

Have you never watched a tyre being fitted? A newly fitted tyre is not automatically airtight just after fitting. A good blast of compressed air is needed, often accompanied with a bit of bouncing and squeezing the tyre to encourage the bead to seat. Car tyres don’t usually need anything more that a good compressed air supply but commercial vehicle tyres or mega tyres for 4x4s need and extra boost to blow the tyre bead out to the rim. This can be from an air tank or by using a flammable gas.

Tim

[Mike Rogers]

ar wheel, when the tyre is removed to repair a puncture and is

Its common practice for tyre fitters to make the initial inflation without the valve core fitted. This allows greater airflow into the tyre to help the tyre bead to bed onto the wheel rim.

Mike

[Rob Morley]

It's called a bead blaster (yes, that's ambiguous) or bead setter, probably other names too. It's just an air reservoir with a big ball valve on it, so you get an inrush of air to (hopefully) set the beads. Starter fluid (ether) is his other tool, popular with off-roaders who use big tyres at low pressure that can easily unseat.

[NY]

Ah, so they just rely on the airflow *outwards* through the valve stem when the pump is then removed being low enough that they can screw the valve in before too much air has escaped? And they can then pump the tyre to its correct pressure with the valve now able to seal as soon as the pump is removed? Fair enough. Sounds a bit dicey, having to fit the valve very quickly before the tyre has lost too much air.

I'll have to watch, next time I have a tyre repaired, if the garage is quiet enough that they do the tyre while I wait. Normally it's "go away and come back in an hour or so" - and even then I often have to wait...

If a tyre has gone *really* flat, I presume you cannot inflate it with a normal pump because the bead/rim seal will have been broken so the air will escape as fast as you pump it in - unless you can feed it in so fast that the tyre fills out enough for the bead to seal. That's why I wondered if tyre beads are designed to be self-sealing once fitted to the wheel, to avoid the need for blast-inflating...

I've not watched the full video, but is it really a road roller? Do those have any tyres? I thought both the front and back "wheels" were metal rollers. Maybe there are some which are steered with rubber tyres and only have one roller.

[Tim+]

Doesn’t really matter once the bead has seated. Once seated it takes force to get the tyre bead off the rim again. The bead isn’t going to fall off the rim the moment the pressure drops.

Unless you’ve driven on the deflated tyre, it’s most unlikely that the bead will have separated from the rim.

Tim

[Mark]

Lovely video of little Chinese girl changing a lorry tyre and using the air blaster with ease

[Rod Speed]

Yep. I managed to get that with my spare, it had gone flat when the normal tyre went flat so the servo pump wouldn't inflate it. By a miracle a mate of mine happened to show up at the servo and could see me trying change the tyre and it was well after all the tyre fitters had closed and it was a wet and frigid winter evening. He took the spare home and inflated it with his compressor and brought it back to the servo for me.

Yep.

Yep, that one does on the front. You can see that at the start.

Nope.

Yep, that one does. Big heavy front wheels, quite an effort or turn them over when removed and on the concrete floor.

[John Rumm]

That is quite impressive with mostly manual tools!

[Harry Bloomfield Esq]

Tyre beads tend to stick extremely well to the rim. Unless you drive a distance on the flat tyre, likely the rim will remain well stuck in place - saws he who has tried to release a tyre from a rim and failed :-)

[SteveW]

The old trick for car sized tyres - which I last carried out about three years ago for a trailer tyre - is to lie the wheel flat, so that your car's front wheel will ride over the tyre and *just* miss the rim. Someone needs to stand on the other edge of the tyre to stop it flipping up and you roll the car back and forth, while they use their hands on the car wing to bounce it a little at the same time. Repeat for the other side.

[Mark]

I change my own tyres on motorbikes, cars and tractors its really not that difficult if you have the correct tools

[Rob Morley]

I've done similar but by putting a bare rim on the car - that places all the weight in just the right place to pop the bead.

[SteveW]

I've never needed the bare rim - and it's not a good idea for me,as we've always had to do it on the road outside the house.