Modern wheels have safety features designed to retain the tyre in its inflated position on the rim, but never the less a significant pressure loss can dislodge the tyre resulting in possible loss of control.
When the tyre deflates it begins to move across the wheel. With nothing to grip it, the edges slip into the middle of the wheel – known as the well. The wheel loses its traction and you may lose control.
The fitting of a well filler, like a Tyron band (see below), may prevent the tyre coming off your trailer or caravan and help you to come safely to a halt. The band fits in the well of the wheel so when the tyre deflates the band prevents the tyre from falling into the well. The tyre remains on the rim allowing the deflated tyre to form a cushion between the wheel and the road surface. The effectiveness of these bands is well established and many insurance companies offer discounts on premiums if you have a set fitted. Tyron bands require specialist tools to remove.
The device shown is a portable Tyron fitting tool. It is light and compact enough to be carried with the wheel changing tool kit. It has been made in response to the comments that in some countries safety bands are unheard of and tyre shops do not have the appropriate equipment to fold the tyre back to refit the bands.
In normal use the tread of a car tyre will wear while the tyre casing or structure generally remains in good condition. A retread is a tyre that has had a new tread applied to the casing.
There is no reason why you should not use a retreaded tyre on a caravan or trailer – in the past they were to be made to the British Standard BS AU 144. It is a legal requirement that retreads must be marked with the words Remould or Retread, the British Standard number and the maximum speed permitted denoted by the speed symbol.
Since 2004 retreads have been subject to European regulations ECE 108 for car tyres and ECE 109 for commercial vehicles, and will be -E- marked to show compliance.
Many retreads are made to specifications that may exceed British Standards – but not all. Be aware that there are unscrupulous dealers about. That said, good retreads can be cheaper than new tyres and should perform equally as well.