Pre 1950s rides of LFGSS: old bikes, vintage rats, classic lightweights

Is there any way, x ray frames for trace of fatigue, etc? that could be done?

Short answer is no.

Longer answer is maybe yes. Surface X-ray reflection can be used to measure residual stress, so if a metal is fatigued to the point that it is about to start failing and is graining up, technically you should be able to see it. However, this is a very specialised technique and I don’t think it’s commercially used yet because it’s very much in its infancy. Also, if it’s got that far that it’s graining up at the surface, I’d wager you’d be able to see it visually first and you’d already have felt the bike getting a bit noodly at the front. XCT would also not be able to give you any indication how long you’ve got left, only if it’s right near failure.

Apols for the nerdy answer! I’m a materials scientist and done quite a lot of work on surface stresses in metals.

I have an uncomfortable and vivid recollection of crack detection in winding gear castings - wiping parts with a dye and blowing french chalk over it. This was an annual event, sufficiently labour intensive to be a job for apprentices* under the arms-length supervision of the colliery engineer.

In theory, dye will be drawn into a surface crack on a clean surface, which would then show up as a stain in the subsequent dusting of chalk. In practice everyone (except the engineer) spent the next week or so with red stained hands, and we never actually found any cracks.

You might be able to apply this method to a frame - it might identify surface cracks in places you can see, it would require some savage cleaning afterwards, and it has all the makings of a good spectator event. Photos if you try it please.

*I was a NCB apprentice in the 1970s...

'Except there's always noises,'

I'm not satisfied unless my bike is silent, even an old machine like the Sunbeam in the thread I mentioned a few posts back.

I will reluctantly make slight exceptions, eg: Resilion brake levers are bound to rattle a bit. I would always want to know the cause of any noise.

I've been searching my memory for frame failure stories, and the ones that stand out are mostly new or recent frames:

1. About a decade or more ago, when carbon frames were relatively new, a clubmate had his carbon frame collapse under him in a road race. He wasn't hurt seriously in the physical sense, but he got very angry with the shop that supplied the frame when they told him it was only guaranteed for 18 months use and as he'd had it for two years he was out of luck!

2. A sponsored cyclo-cross rider I know (I'm not going to mention his name since he is still working in the sport) broke an aluminium frame and his collar bone (at the same time) He fell out badly with the sponsor because they still wanted to hold him to a contract to use their fragile bikes which he, not unnaturally, no longer trusted.

3. Largely forgotten now, but Louison Bobet suffered a broken frame on the Izoard in the 1948 Tour while trying to defend his yellow jersey against Bartali. This is a fascinating story which I will leave for another day.

Of course it must be admitted that when the outcome of a high level race is affected by mechanical failure it's bound to get attention and be remembered, whereas when my ancient frame gives up the only person who is certainly going to hear about it is my other half who will be called on for taxi services.

Perhaps the safest option is a middle aged frame which has proved itself in use but which cannot be said to be worn out, but I think we have to recognise that nothing in cycling is completely safe.