wheel - tyre problem

omri

Hi,

Any clue what's the problem here ?

My guess wrong tyre size.

uberwolf

have you tried inflating this?

sometimes the beading/tire just won't sit right without a little bit of inflation /deflation and just jigging it around. Be careful that the tube isn't pinched when you're doing that much.

omri

I have. My friend has a bike and one of tyres looks like that. Both tyres are different but have same size. I brought him two mine I had laying around which are bit different but 622 size is the same. And they fit same way on the back wheel. So inflating made no difference. I even checke the rim to see maybe it's egg-shaped but it looks fine.

Keep_Her_Lit

It looks like the tyre just hasn't seated properly on the rim. Some tyre/rim combinations seem more susceptible to this problem than others.

I would try removing the tyre, then smearing the bead and lower part of the sidewall on each side of the tyre with a thin film of washing up liquid. This will reduce the friction between the tyre and rim and may help the bead to pop into place. It has worked for me before.

If your rim is in good condition (i.e. the brake surfaces are not heavily worn), you can also slightly overinflate the tyre to help it pop into place, then reduce the pressure again before riding. Don't overdo it though, or the rim may end up damaged around the valve drilling, where it is weakest.

As for sizing, if both the tyre and rim are marked 622, their diameters should be compatible. Widths shouldn't be a problem unless you're trying to fit a very narrow tyre to a wide rim or vice-versa; from the pic, that doesn't seem to be the case.

Schnell

Tis just a flat spot on the tyre, either badly put on or a crap tyre, in my experience 27" (not your size) tyres often have them as a lot of them are poor quality being put onto oldish bikes. It's a bit rarer that it'd happen 28"/622/700c (your size) tyres so it's probably just needs to be taken off and remounted, having the tube a bit inflated when you're mounting the tyre tends to make the difference.

"Flat spot - Usually applied to tires or bicycle wheels, this refers to a condition in which the radii of a section of the tire or wheel are shorter. In the case of tires, this is most often because the tire is not mounted well. It must be deflated, manually adjusted and reinflated. Other reasons for a flat spot in tires is poor quality, or an incorrect fit." From http://www.bikewebsite.com/bikeof.htm

omri

Will have to try again as the tyre has been fitted with inflated tube. And actually my friend reminded me that the new tyres we put on both wheels have exactly same issue now. Before it was only rear wheel problem.

Paul Kiernan

It looks like the tube at the base of the valve is trapped between the rim and the tyre, preventing the tyre from seating properly on the rim.

Loosen the outer nut that holds the valve tight against the rim and check if you can push the whole valve right up into the tyre - if you can't, it's trapped and you may need to (partially) remove the tyre to free it. Once it's free the tyre should pop down tight against the rim.

manwithaplan

Paul Kiernan wrote: »

It looks like the tube at the base of the valve is trapped between the rim and the tyre, preventing the tyre from seating properly on the rim.

Loosen the outer nut that holds the valve tight against the rim and check if you can push the whole valve right up into the tyre - if you can't, it's trapped and you may need to (partially) remove the tyre to free it. Once it's free the tyre should pop down tight against the rim.

This can happen if you tighten the valve nut before you inflate the tyre. Did you do this by any chance?

omri

manwithaplan wrote: »

This can happen if you tighten the valve nut before you inflate the tyre. Did you do this by any chance?

No nut on the valve, nothing trapped anywhere. Everything is done bu the book and the result is still the same I'm afraid. It sits fine except that particular part. Same thing with both wheels.