Magnesium Wheels

Magnesium wheels do have a finite life. From what I understand, most racing teams only run them for about a year, because they develop internal fatigue cracks. Those wheels are a lot lighter than street wheels though. It depends on the design of the wheel, the alloy that it's made from and what sort of abuse they get. In the case of your wheels, you would probably have to ask an expert. Are you sure that they're real magnesium?

holy smeg! i know they are prone to going porous, but i've never seen anything like that! most race wheels aren't designed with road use in mind, so this is another thing to consider. Especially track wheels that are meant for smooth race tracks and not pot holed roads, they tend to be softer and easy to put out of shape. wheels meant for rally use, i would have more faith in.
With your wheels, i would be inclined to inspect them yourself with the tyres off. Check for corrosion, if there is any check to see if the metal underneath has gone soft. I find proding with an old screw-driver works fine! even slight pitting on the bead will allow a tyre to go flat slowly, so a slow puncture doesn't always mean dead wheel. if they generally look solid, then they would imo be worth sending off to see if they could be refurbed.
another good test is with the tyre off, hold the wheel in one hand and tap the inside of the barrel with the handle end of a screwdriver. The wheel should ring like a bell. If the wheel has major cracks in it, it will sound dead when hit, i.e. it will not resonate. This will only give a rough guide to the wheels condition though.

Interesting, and scary !!, reading.

Thinking about it, the only reason I 'know' they're magnesium is because that is what the person I bought them off told me.

I think I'll take them off and inspect them, won't be able to do that until I'm back in the UK and have collected the spare wheels from my parent's though ...

Thanks for positive comments re car

What sort of place does x-ray'ing of wheels?

See generic term 'Slot-mag'

Well they've been on the car now for 3 years including heavy winter use. Still in good condition with only a bit of paint flaking. I'm coming to the conclusion that they're not magnesium - hopefully. I really like them, intention is to get them repainted black, with polished bare metal face and change the rear tyres for some lower profiles like the front.

But before I get carried away, at the next opportunity I'll get them off and inspected and find out what they really are.

Thanks for all the help.

Shouldn't think they are magnesium as they have "bare" uncoated rims. This would be a problem with a magnesuim wheel as they will corode/deteriorate when exposed to atmosphere. Mag' wheels would be chromate diper then painted/coated all over.