With older wheels a common problem can be air loss.

If the tyre does not have a defect or a puncture, and the wheel is straight, this air loss can be caused by corrosion between the tyre and the wheel. This corrosion causes an uneven surface and a breakdown in the seal between tyre and wheel and allows air to escape.

Having removed the tyre, the solution involves removal of all paint and corrosion in the seal area, re-priming and painting of the area under the tyre. This is followed by refitting and balancing the wheel and tyre with rubber valve replacement.