Innertubes

[yellowpinky]

I recently had some new tyres fitted. I have two 4.5J's two 5J's (the ones with a safety bead from Minor Developments) and the spare which is a standard rim. All the tyres were fitted tubeless except the one on the standard rim. This rim had a tube in before it was replaced and it's the garage's policy to replace it the same as how it came in. But it got me thinking and I wondered if all tyres would have been safer with a tube. So what's the score with this? What's the best option?[frame][/frame]

[autolycus]

The garage is certainly right according to the relevant British Standard (BS AU 50), which says:

"Drop Centre Rim; standard

This rim should not be used for tubeless radial tyres, unless a tube is fitted"

I looked into this in connection with fitting radials to another 1950s classic, and found it very difficult to get an authoritative view on why this sentence is included in the BS. Tyre makers referred me to wheel makers, and wheel makers don't exist any more - in the sense of firms like Dunlop's wheel division. The best advice I could get was from an older engineer who had formerly worked for Dunlop, and while he surmised that it was because of the risk of de-beading, he couldn't cite a single incident where it had occurred. I suppose one can envisage situations where a car slides hard into, say, a kerb, but by then a mere matter like a deflating tyre is perhaps not your top worry. I must say that I find it difficult to believe that you could generate enough lateral force at the tread of a tyre to cause the bead to slide gracefully into the well, unless the tyre was already deflated. A back of envelope sum suggests that the air would be pushing the relevant bit of tyre outwards with a force of at least 500lb, or 2kN for our younger readers, and then there's the stiffness of the sidewall and the firmly stuck bead-to-wheel also keeping things in place.

As for using tubes in tyres marked "Tubeless" - I'd check with the tyre maker, not a yoof in a tyre-fitting emporium. My experience with inner tubes in tubeless tyres in Range Rovers (with the usual corroded alloys) is that tyres with pronounced inner ribs chew quickly through tubes. Others have been luckier.

I'll be "risking" tubeless radials on a big, heavy, classic with drop centre rims, on the grounds that the risk for me of the tyre de-beading is less than the risk of it deflating rapidly in the event of a puncture in a tubed tyre. YMMV, and this advice is worth exactly what you have paid for it.

Kevin

[bmcecosse]

They will be fine tubeless.

[mike.perry]

I have been running my Series MM on tubeless radials for over 30 years with no problems and I am not noted for my gentle cornering.

[PSL184]

The only problem I have found in running tubeless tyres is on "riveted" rims whereby the air can seem to escape from the joints more readily than with the "welded" rims.....

[aupickup]

tubeless is fine, i have run moggies without tubes on standard rims and wide rims for years

[Fozz]

Have had problems with my tyres losing pressure, and went to tyre fitters today. They said that the reason for the loss of pressure is that I have the wrong type of rim for tubeless tyres, and am losing air from the tyres when cornering. They recommend putting tubes in to solve the problem.

[aupickup]

have not lost pressure in mine and i use mine most days, around 7500 miles a year and they have been fine without tubes

[Fozz]

I think I will try it, as I've had the problem for ages and I lose pressure equally on all four wheels. The tyres were brand new when I bought the car in April, and haven't done very many miles since. The wheel rims are in good condition too, and don't lok rusty (on the outside at least!)

[mike.perry]

Check the condition of your wheels carefully, remove any signs of rust inside the rim. My local fitter smears some sort of adhesive around the inside of the rim, maybe that helps to seal the tyre.

[autolycus]

Have had problems with my tyres losing pressure, and went to tyre fitters today. They said that the reason for the loss of pressure is that I have the wrong type of rim for tubeless tyres, and am losing air from the tyres when cornering. They recommend putting tubes in to solve the problem.

Have you tried laying the wheel down flat, and dribbling some soapy water to fill the little "V" gap between tyre and wheel? Leave it for ten minutes, then look for bubbles. [Looking back, this is exactly what Roy suggested in the previous thread, and he's usually right ] Turn the wheel over and repeat. Do it for all five wheels Then do the check round the valve stem that he and I suggested before. Finally, replace the wheel/tyre that leaks worst - the one you said you found at 10 psi - with your spare, and put the leaky one in the boot for a couple of weeks. Then check its pressure again.

I would be astonished if cornering could break all four bead seals sufficiently to let some, but not all, air out.

It's much more profitable for a tyre fitter to flog you over-priced inner tubes than to go through the slow process of stripping, rubbing down, priming, and painting rusty wheel rims. Most of them can't even be bothered to give the rims a token swipe with a wire brush to knock the biggest flakes off. Outside wheel condition gives little clue to the state of the surfaces the tyre seals onto, as very few owners seem to want to master the fairly straightforward task of removing and re-fitting tyres, so will assiduously paint the visible bits the correct shade of magnolia while ignoring the functional bits of the wheels.

And the tyre fitter can put his hand on his heart and say "I'm complying with the BS" by fitting tubes. Actually, you did well to find a tyre fitter who sells tubes - one well-known chain doesn't stock tubes of any size.

Following Mike's comment about adhesives - don't encourage them Mike! It's hard enough breaking a bead sometimes when they've used the the proper stuff - essentially a soft soap - we don't want people who read this using Araldite!

Kevin

[newagetraveller]

The trouble with innertubes is that they rub against the inside walls of certain tyres. Eventually they may wear so much that they wear through and then the tyre deflates rapidly. If you have four new tyres all with new innertubes several of them can deflate within a worryingly short space of time i.e. a week.

[Fozz]

Am now not sure about these inner tubes! My husband says it makes sense to fit them, he uses tubes on his 1957 motorbike. His reasoning is that when the car was manufactured it would have been fitted with tubed tyres which does make sense, but I can see why putting tubes into modern tubeless tyres wouldn't work.
The tyre place haven't been back to me to say that the tubes are in (they ordered them for me), so wondered if I should get a second opinion somewhere else. Have been pumping the tyres up before every trip and by the next day they are back down to 20 psi. I think I must have made a mistake in saying one got down to 10, they all seem to deflate at exactly the same rate. She is going in for MOT tomorrow, the garage said I should go to a tyre fitter rather than them to sort the tyre problem out, but might ask their advice.

[mike.perry]

The motor bike would have had spoked wheels which I assume would need tubes. Have you tested the valves for leaks by using the time honoured method?

[Fozz]

No I haven't checked the valves, I am ashamed to admit that at the moment I don't have a jack for the car, so can't get the wheels off - also would need hubby's help and he is very busy at the moment. If it is the valves leaking what would be the solution?

[mike.perry]

No need to remove the wheels to check the valves, just remove the valve caps. If any are leaking the valve core can be removed and replaced with a new one. Your tyre pressure gauge may have a tool in the end for unscrewing the valve core or you can get dust caps designed to unscrew the core. I always keep one on my spare. You should be able to buy a tin of valve cores at any motor accecssory shop.
Go and buy yourself a decent scissor jack or you are going to feel silly if you get a puncture and can't remove the wheel, don't bother with the original type of jack.

[Fozz]

Am going to get a jack asap, luckily she passed MOT today so no extra expense there thank goodness. Will have to see about new valves then, hubby still says just fit inner tubes, I think we are about to have a domestic over this!!

[mike.perry]

Probably won't need valves but worth checking them, anyway a set of valve cores is cheaper than a set of inner tubes.

[katy]

I noticed that nobody explained "the time honoured method" to you how to check the valves.
1. Remove the valve cap.
2. Put a little spitt on your (clean) finger.
3. Put the spitt on the end of the valve stem and watch for bubbles.
Your valve core might just need tightening, rather than replacing.
Always check that.

[mike.perry]

I was waiting for the question to be asked