I rarely ever ever get punctures, but fate has just made a timely intervention...
Bought a new tube yesterday to fix a completely flat rear. Got home in the evening and took the wheel apart to give it a good clean and to fit the new tube. Then I noticed what's in the photos.
For a while, when using the rear brakes, there's been a juddering at one point of each rotation. A slight bulging of the rim seemed to be the culprit.
But the real scary monster causing the rim bulge is the giant spreading fissure lurking under the rim tape
All the 'eyelets' around the nipples are rusting. The main fault line crack in the rim runs at least 5 spokes and from it in each direction, there's a noticeable finer line spreading out around the whole rim.
Basically, the crack has developed and has been spreading as I've been riding – the rim is steadily splitting itself in two. I only discovered this by chance, as I rarely have any flats to repair. Wonder what state the front rim is in, with its now concave rims.
The FIRs have given rock solid service over 23 years – not bad.
It's time to get some new bits and build some wheels
Clockwork A309 A0163
Wanted: Onza RCR 160 bar ends