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I'm just refurbishing these GB alloys and I will be fitting the Falken tyres I got from Chris (999 ORX). As they do not have a ridge on the rim I was wondering what people thoughts are on the need to fit inner tubes when fitting the tyres?

By no means essential, but probably a safer bet.

I don't run tubes in my GBs and never had a problem either rallying or autotesting (yet!)

From Avon competition Dept.


Tube fitment

Guidance on tubes in tubeless road tyres

Tubeless tyres in good condition, both new and retreads, fitted to the appropriate wheels and operated correctly, do not need inner tubes however there are some circumstances when it is useful to use a tube. When tubes are fitted, it is important for the user to understand the potential drawbacks.

When a tubeless tyre is punctured, the penetrating object is gripped by the inner liner (the built-in tube) and thus air loss through the penetration will be gradual. By contrast, when a tube type or a tubeless tyre fitted with a tube is punctured, once the tube is penetrated, air loss will normally be sudden. In this case, air will rapidly escape through the valve hole in the wheel and between the tyre beads and the wheel which, with a tube fitted, no longer provides a hermetic seal. Sudden pressure loss in a tyre can result in bead dislodgement and a loss of vehicle control.
When a tube is fitted to any tyre, it is important that the inside of the tyre is carefully examined to ensure that there is no feature which could cause premature tube failure due to cuts or chafing. Such examples are:-

Any tire manufacturer’s paper or plastic identification labels must be removed and label indentations buffed smooth.
Damage to the inside of the tyre, possibly due to a previous penetration or repair can lead to chafing of the tube and subsequent failure.
The increased thickness of the tyre / tube assembly can cause running temperatures to increase and could under prolonged conditions cause premature tyre failure.

Not withstanding the potential hazards, there are circumstances when the use of tubes may be recommended. The following points should be noted:

Inner tubes must be fitted to all tyres that are NOT marked as “Tubeless” and to all tyres marked as “Tube Type”.
Always use a new tube in a tyre with matching size marking.
NEVER install a non-radial tube in a radial tyres
Inner tubes should also be used:

Where tubeless tyres are fitted to non-safety wheels or multi-piece wheels.
Where tubeless tyres are fitted with wire spoked wheels where air could otherwise escape through the spoke holes in the wheel.

Inner tubes should not be used as a means of repairing a puncture to a tubeless tyre, as a proper repair should be carried out to retain the tubeless properties of the tyre.
The fitment of tubes to tyres of 65 series and lower is not recommended.
If correct size tubes are not available, an alternative size tube should NOT be used.

Wire wheels, multi-piece wheels and some single piece wheels designed for tube type applications CANNOT be used as tubeless fitments and the use of a tube (regardless of whether the tyre is “tube type” or “tubeless”) is ESSENTIAL FOR SAFETY. Always use tubes in such fitments.
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I will add one more consideration based on my own past experience with tubes... but on steel wheels. Unless your tubes provide a secondary seal to the rim at the valve stem hole, water can get between the tube and rim. Inside the rim this can lead to corrosion. This is not a big deal if you always plan to run tubes. However, that was not my plan when I installed tubes and my decision allowed rust to form which meant that those rims would forever be used with tubes (or at least until I decided to strip and refinish the rims).

Just make sure there are no imperfections inside the tyres from the moulding process, they can pierce the inner tubes.

I've had a huge amount of trouble with my steel wheels going flat both with inner tubes, and without, so I'm not sure which is better? When the inner tubes did go flat it was very quick too!

Good and valid comments from minimans and dklawson.

I would add: the valve hole is different for tubed and tubeless rims.

If you put a tubeless valve in a tubed rim, it will leak, and can cause rapid/sudden deflation -which doesn't make for a good day out...

If you put an inner tube on a tubeless rim, the hole can cut the valve out of the tube. With similar results.....

The air pressure in the tyre will hold it in position.
-You are only likely to have a problem if you're running very low pressures (such as 10psi). But, why would you...
(In the event of tyre deflation, the bead is not going to hold the tyre in position anyway.)

Well it appears it is a unanimous vote for no tubes. My main concern was that there was no ridge for the bead to locate on, hence why I asked what peoples opinion was.

After all the advice, and GrahamCs experience I will be going without tubes. I had not considered the chance of chafing between the tube and tyre and on checking the Falkens there is a bit of ribbing on the side walls.

Hopefully the wind will have dropped tomorrow and I can get the top coat on the rims, I'll post some shots when they are done and fitted.

Thanks for all the replies, much appreciated.