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Recently, I had a problem with the back rim (the axis) and the guy who repaired just replaced the rim.

After few weeks I tried to repair a flat tire, but I found myself unable to remove the tire to change the tube. After two or three hours of fight I found out that I had damaged the tube and the tire, and I decided to just tear the tire apart. Even doing that was difficult.

So after that, I tried with 32-622, 35-622 and 37-622 tires and none of them fit. Impossible. Not even the first bead of the tire, which is supposed to be easy.

Then I decided to measure both rims (the one that wasn't replaced and the affected one), and they seem to have the same diameter as well as the same width. The only matter in which they differ is the well depth. The "good" one has about 12mm of depth, while the one I can't mount has like 8mm.

Can anybody please suggest which tire sizes should I buy? This is the rim that I can't mount. 8mm deep well Both rims next to each other.

  • 1
    Are you using proper tire levers try to mount the tire? Looks like you've done a little damage to the rim you are holding in your hand in the bottom picture. Also, are you sure it's not a 27 inch wheel? The difference is in diameter would only be about 8mm, which might be hard to notice when using a measuring tape, but would make a noticeable difference when trying to mount tires. – Kibbee Jul 11 '15 at 14:41
  • Hi Kibbee, thanks for your comment. I measured carefully both rims again. From edge to edge, there is maximum 1mm of difference. And yes, you're right, unfortunately I damaged the rim when trying to remove the old tire. I'll try to sleek those bits. And about the levers, well, as far as I knew they should not be necessary when trying to put the first bead. – mdelolmo Jul 11 '15 at 15:21
  • What size of tires were mounted on the tires before? – Batman Jul 11 '15 at 15:40
  • Batman: 35-622. But I believe that was not its size. It was almost impossible to take it out. – mdelolmo Jul 11 '15 at 15:51
  • So. I measured both rims again, but this time the circumference of the bed. The fitting rim seems to be 1 inch (~2.5cm) shorter. Maybe I need a 630 tire. – mdelolmo Jul 11 '15 at 16:48
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Those appear to be hooked rims,(difficult to see in the pic) which are almost all iso-622. iso-630 rims are usually straight sided rims and used only on 25-50 year old road bikes. Occasionally tires are just made with tighter bead wires. You must fully deflate the tire and break the bead seal all the way around on both sides so that the edges farthest from where you are working can slip into the center well without resistance.

You should not expect to put the first bead on fully without levers, it does happen occasionally but don't expect it. Technique is a big thing but I can't help you with that without being there.I have done some ten thousand bike tires in the shop, manufacturing tolerances are quite wide, not much you can really do about it other than practice.On the plus side, tight bead wires are less likely to let the bead pop out and cause the tube to blow out, which can happen if the tire is near max pressure in the cold morning and then parked directly in the afternoon sun. It sounds about like an M-80.

  • you can still buy new (perhaps they are all new-old stock though) 630 rims and tires though – Patrick Zissou Feb 20 '18 at 20:15

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