How are tyres without an inner tube inflated? (non boaty)

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peter2407

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My daughter has a 4 wheel go kart that I tried to inflate the tyres on. I expected there to be an inner tube as there is a valve, but cant find one. How does one inflate a tyre when there is no contact between it and the rim where the valve lives?
 
peter2407 said:
My daughter has a 4 wheel go kart that I tried to inflate the tyres on. I expected there to be an inner tube as there is a valve, but cant find one. How does one inflate a tyre when there is no contact between it and the rim where the valve lives?
Click to expand...

You need an air line with plenty of air flow to inflate a tubeless tyre.

Surely you must have seen them do it in a tyre depot

I think tyre fitting depots may fit a belt round the tyre sometimes. You could try cable ties

With tubed tyre the valve is part of the tube. With tubless it is fitted to the rim
 
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I have used a ratchet strap tightened round the othside of the tyre to create the seal. Once you have a bit of air in you release the strap and inflate normally
 
As an apprentice mechanic in the 1960's when tubeless tyres were a new thing and tyre changing machines were a long tine in the future, I was shown how to remove and fit tubeless tyres with a Stennor bead breaker-sort of a big "G" clamp-two tyre levers and a rubber hammer. A pot of soapy water and a paintbrush featured largely in this.

Basicaly the trick is to see which part of the wheel has the biggest bead seat. The bead seats are where the tyre sits on the rim. For example, on a proper Mini the wheels had to be designed with a large bead seat on the outside and a narrow one on the inside. The bead of the tyre has to be moved to the well in the centre of the wheel. The Stennor bead breaker was used to break the bead seats from the rim and move each bead seat to the well. The dimensions of the wheel means this well has enough depth so the first bead, using the tyre levers, can be lifted over the rim. Continuing with the levers, little at a time, and the first side is off. Now the lever is introduced from the front of the wheel, under the bead seat and a strong pull will lever the bead seat over the wheel edge. This is where the rubber hammer comes in. Whacking the tyre bead seat either side of the lever soon has the tyre off.

Re-fitting, or fitting a new tubeless tyre is easier than removal. The bead seats are lubricated with the soapy water, the wheel held in one hand and the tyre is placed not quite vertical with one edge on the ground. The wheel is then banged into the tyre, whereupon, if the lube was good, it will be inserted about 2/3rds of the way. The wheel is laid down flat with the tyre uppermost and the bead seat whacked with the rubber hammer untill it is on. The other bead seat is then trodden-well thats how I do it-into place and the rubber hammer weilded untill that one is on. Ankles are in a bit of danger during this operation.

Once the tyre is on the rim, the bead seat must be persueded on to the larger of the two portions of the rim. Once it is on an inch or two the wheel is reversed, the tyre edge leaned against a vertical surface and the centre of the wheel pressed just enough to make the bead seat contact the other side of the wheels seating area. With high pressure air-often without the valve core in the valve-air pressure should seat both sides of the tyre on the rim.

The reason for all this rigmarole is that tubeless tyres are constructed to tighter clearances in the bead seat areas-which were larger than tube type tyre beads-and they have an impervious membrane incorporated during their complicated manufacturing process.

So, to get back to the OP.

You must fit one side of the tyre bead seat onto the seating area of the wheel. Once this is done, gentle pressure in the centre of the wheel might-note might-allow the opposite bead seat to seal when high pressure air is added. A rope can be tied tightly round the centre of the tyre, a large screwdriver or tyre lever pushed under and subsequently twisted to squeeze the centre of the tyre, causing the bead seats to engage. Be gentle with the air-I witnessed a tyre lever clouting the operators shins big time once as the pressure caused the rope to untwist.

Of course, modern tyre changing machines make this obsolete. Good Luck!
 
Rotrax has said it all basically though make sure the bead seats are clean with some lubricant on the beads and a good flow of air to pop the non seated bead into its seat.
 
rotrax said:
As an apprentice mechanic in the 1960's when tubeless tyres were a new thing ................................ For example, on a proper Mini the wheels had to be designed with a large bead seat on the outside and a narrow one on the inside.
Click to expand...

Interesting. I have Mini wheels on my trailer and I think there's a spare rim in the shed. I must take a look at it. I'd not noticed the difference but then I am not in the habit of removing or refitting tyres myself!
 
peter2407 said:
My daughter has a 4 wheel go kart that I tried to inflate the tyres on. I expected there to be an inner tube as there is a valve, but cant find one. How does one inflate a tyre when there is no contact between it and the rim where the valve lives?
Click to expand...

This is what you need

One of these

or
 
rotrax said:
As an apprentice mechanic in the 1960's when tubeless tyres were a new thing and tyre changing machines were a long tine in the future, I was shown how to remove and fit tubeless tyres with a Stennor bead breaker-sort of a big "G" clamp-two tyre levers and a rubber hammer. A pot of soapy water and a paintbrush featured largely in this.

Basicaly the trick is to see which part of the wheel has the biggest bead seat. The bead seats are where the tyre sits on the rim. For example, on a proper Mini the wheels had to be designed with a large bead seat on the outside and a narrow one on the inside. The bead of the tyre has to be moved to the well in the centre of the wheel. The Stennor bead breaker was used to break the bead seats from the rim and move each bead seat to the well. The dimensions of the wheel means this well has enough depth so the first bead, using the tyre levers, can be lifted over the rim. Continuing with the levers, little at a time, and the first side is off. Now the lever is introduced from the front of the wheel, under the bead seat and a strong pull will lever the bead seat over the wheel edge. This is where the rubber hammer comes in. Whacking the tyre bead seat either side of the lever soon has the tyre off.

Re-fitting, or fitting a new tubeless tyre is easier than removal. The bead seats are lubricated with the soapy water, the wheel held in one hand and the tyre is placed not quite vertical with one edge on the ground. The wheel is then banged into the tyre, whereupon, if the lube was good, it will be inserted about 2/3rds of the way. The wheel is laid down flat with the tyre uppermost and the bead seat whacked with the rubber hammer untill it is on. The other bead seat is then trodden-well thats how I do it-into place and the rubber hammer weilded untill that one is on. Ankles are in a bit of danger during this operation.

Once the tyre is on the rim, the bead seat must be persueded on to the larger of the two portions of the rim. Once it is on an inch or two the wheel is reversed, the tyre edge leaned against a vertical surface and the centre of the wheel pressed just enough to make the bead seat contact the other side of the wheels seating area. With high pressure air-often without the valve core in the valve-air pressure should seat both sides of the tyre on the rim.

The reason for all this rigmarole is that tubeless tyres are constructed to tighter clearances in the bead seat areas-which were larger than tube type tyre beads-and they have an impervious membrane incorporated during their complicated manufacturing process.

So, to get back to the OP.

You must fit one side of the tyre bead seat onto the seating area of the wheel. Once this is done, gentle pressure in the centre of the wheel might-note might-allow the opposite bead seat to seal when high pressure air is added. A rope can be tied tightly round the centre of the tyre, a large screwdriver or tyre lever pushed under and subsequently twisted to squeeze the centre of the tyre, causing the bead seats to engage. Be gentle with the air-I witnessed a tyre lever clouting the operators shins big time once as the pressure caused the rope to untwist.

Of course, modern tyre changing machines make this obsolete. Good Luck!
Click to expand...

I did that once, just to try it. Never again...
 
RichardS said:
I would have expected that the nozzle would get trapped between the tyre and the rim .... but obviously not as that wouldn't be a great seller. :o

Richard
Click to expand...

Commonly known as a bead cheater/cheetah and pretty much every mobile tyre fitter will have one.

To the OP.. get yourself down to a local tyre place as you could do some damage if you dont know what you are doing. They probably wont even charge you. (but some chains might say you need 4 new tyres, a radiator and a set of shock absorbers)
 
Tzu said:
Commonly known as a bead cheater/cheetah and pretty much every mobile tyre fitter will have one.

To the OP.. get yourself down to a local tyre place as you could do some damage if you dont know what you are doing. They probably wont even charge you. (but some chains might say you need 4 new tyres, a radiator and a set of shock absorbers)
Click to expand...

And new discs and pads...........................................
 
Avoid anything explosive!!

Get the tyre seated on one side by putting your foot against the wheel while holding the tyre, then turn it round and apply air pressure, while gently pushing the wheel in the other direction. It will seal enough to get the first bit of inflation, then the rest is easy. You might get a pop when it finally seats!!

I have fitted quite a lot of tyres...
 
Similar issues on our DS (like Rotrax of this parish and his minis I'd clarify it as a 'real one ' not the modern pastiche - don't get me started) some variants of which are tubed and some not. A shade-tree solution can be to artfully arrange a bin liner around the inside of the tyre and rim but the ratchet strap around the outer circumference of the tyre works well especially if one doesn't have to hand the luxury of a gert great blast of air to get things going.
 
VicS said:
Interesting. I have Mini wheels on my trailer and I think there's a spare rim in the shed. I must take a look at it. I'd not noticed the difference but then I am not in the habit of removing or refitting tyres myself!
Click to expand...

Modern wheels for tubeless tyres have "safety land" (I think that's the term) which are flat bits of the cross section by the rim so that if the tyre deflates and the bead comes away from the rim it doesn't immediately fall into the well in the middle of the wheel. Older wheels (including those from my Herald and DS) don't have this, so your old Mini ones probably don't either.
 
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