Is this tire properly fitted on the rim?

Question

My tires are 622 x 38C, and on the rim it says 622 x 21C (m̶i̶n̶i̶m̶u̶m̶ ̶t̶i̶r̶e̶ ̶w̶i̶d̶t̶h̶ ̶t̶h̶e̶ ̶r̶i̶m̶ ̶s̶u̶p̶p̶o̶r̶t̶s̶,̶ ̶I̶ ̶b̶e̶l̶i̶e̶v̶e the rim width). These tires cost around 18 dollars each.

I've spent some time on:

• making sure I haven't pinched the tube and there is no foreign object between the tire and the rim;
• deflating, adjusting the bead, trying to straighten the tire, reinflating;

The rim is true, the bead seems fine, yet the tire has a noticeable wobble (~2mm I would say):

This is how the bead looks:

These are the original components of a 170USD bicycle I bought from Decathlon a month ago. They have bicycle mechanics and a repair shop; but I guess they don't spend a lot of time fine tuning the bicycles before selling, especially the cheaper ones.

The front tire (which I haven't touched yet) wobbles a bit more; the rim is also 1-2mm out of true.

Will this tire wobble wear down the bearings faster, or other components? Or is this amount considered normal, and won't do any harm? Is this as true as you can get on such a cheap bicycle? Should I spend more time trying to adjust or leave it as it is?

Answer 1

I'll answer all your questions in order.

1) "Will this tire wobble wear down the bearings faster, or other components?" -Nope, this wobble will do pretty much nothing to the rim. If anything, you will feel the slightest of 'floating' (the only way I can describe it, the bulge ever-so-slightly lifting the bike when you go over it.)

2) "is this amount considered normal, and won't do any harm?" -Any tyre wobble is not classed as normal, though it will not do any harm to you, the bicycle or your bike's performance.

3) "Is this as true as you can get on such a cheap bicycle?" - The bicycle has nothing to do with the tyre. If the bike was £120, you can still get £80 Continentals. The tyre's quality, however, is quite a big factor. If you bought them for £12 a piece, there's a high chance that there may be minor defects.

4) "Should I spend more time trying to adjust or leave it as it is?" -Leave it. If anything, you risk doing more damage to the tyre/rim, constantly playing with it.

Ride around on this tyre for a couple days. In my experience with cheaper tyres, they'll settle down. It's usually due to storage/transit. Re-inflating usually gets rid of any deformation, though not always. Riding it for a while will eventually get it to even out.

If the tyre is damaged, you'll usually notice a very major bulge. If you take an innertube and inflate it, looking at the valve, you'll notice it has a weird shape around where the valve is. It'll look somewhat like that, but on the tyre.

Answer 2

It looks to me that your tire is not properly centered on the rim. Probably neither the rim nor the tire are faulty, but they require more effort to center the tire.

The first thing you should check is whether the rim tape is well-centered. One of the main reasons why a tire cannot center on the rim is that the rim tape has creeped up at some points towards one side of the rim.

When the rim tape is centered, you can put the tire and inner tube back on. Center the tire roughly with your hands and check that the inner tube is nowhere squeezed between tire and rim. Pump the inner tube to the maximum pressure indicated on the outside of the tire. You will probably hear some plops. At the maximum pressure the circular rim line on the tire should be at the same distance to the rim everywhere. If so, the problem if solved. Now reduce the inflation pressure to a value more comfortable for riding.

If it is not, there is a final trick. Release the pressure and wet both the outside walls of the tire and the rim hooks with a solution of a detergent using a cloth. A few drops of dish washing liquid in about 100 ml of water is good enough. Apply it generously to all surfaces without splashing it around. Now again pump to the maximum pressure. The soap should facilitate the tire beads to slide into the hooks of the rim.

See also "What can be done if the tyre cannot be centered?" on https://www.schwalbe.com/en-GB/montage.html

PM. For a 622x21C rim, the 21C stands for the rim width, not the minimum tire width. According to Schwalbe's "Which tyre fits which rim?" the minimum tire width for a 21C rim is 35 mm. See https://www.schwalbe.com/en-GB/reifenmasse.html

Answer 3

Mounting tires:

Check the rim tape/strip. Check the rim bead seat area.

Put a bit of air in the tube before attempting to mount the tire.

Put the first half of the tire on the rim. Put the tube into the tire. Start with putting the valve into the rim and stuff the tube into the tire. If needed let some air out ( not too much, you want it to have a basic round shape. ). This will keep it from getting pinched between the tire and the rim.

Starting away from the valve area, start pushing ( by hand only, no tools ) the second bead of the tire over onto the rim. the last ( and hardest, resist the urge to use tools, even plastic tire tools can hole the tube ).

Now you will have the valve area to push on. Do that, yes it will be a bit hard on your hands. Keep the valve area as the last to go on. Once the tire is on all the way, push the valve up into the tire as much as you can without loosing it. This will un-pinch the tube there, if it is pinched. If it will pinch, the last place you push over is likely to be where.