Hi, Just joined the forum and I'd like to ask if anyone has had any problems with tyres on the special alloy rear wheel of Spartamet/Saxonette motorised bikes. It is marked 24 x 590 and when I bought the bike it had a cheapo 37 x 590 tyre, which I changed for a Schwalbe Marathon 42 x 590 puncture resistant tyre (and one on the front too). I then went for a 3 mile ride, and just after I got off, the rear tube exploded with a tremendous bang. I thought that was a fault in the tube, but on my next ride the tyre came off the rim without the tube exploding. I'd checked before buying the Schwalbes, and they were recommended as the best type and size for the Spartamet. Funny thing though, they go on the wheel quite easily, without even needing tyre levers. Other people have said they're normally really tough to get on, because of the reinforcement. I've tried two, so I can't see it being a faulty tyre. I've reverted back to the original 37 x 590, and they stay on fine, and need levers to get them over the rim. Here's a photo of the cross section of the rim, together with the markings on the tyres. As you can see, they're all clearly marked as "590", so I'm mystified. Any one had any similar problems with bike tyres ?