Strange tire problem with LX rim

I have twice now put a new tire on my LX rear rim. One tire was the stock Kenda tire, the other was a Schwalbe Marathon. Each time, I was unable to get the tire to sit 100% correctly in the rim.

In each case, a small part of the white stripe running around the circumference of the tire (approx. 5 cm in length) was not parallel to the rim. Instead, it was curved up and away from the rim, like a bump.

The tire was not bulging out … it was just “raised” out of the rim slightly. Somehow, the tire bead does not seem to be engaging with the groove properly.

On casual visual inspection, the rim does not seem to be bent or wobbly. Also, I tried rotating the tire to see if it was only one spot on the rim, but it occurred at different spots. But only in one spot at a time.

Has anyone heard of such a thing before? I never had this happen with the 5.x rim (or with any other bike rim, for that matter).

Thanks
StridaD

I always install and pump up tires on my Strida with the bike lying down, so the wheel is horizontal and no weight acting on the tire. Then when there is a tiny bit of air in (say 10psi) I check the tire is as even as possible (its rare for it to be perfect), then pump up more until its full.

Then for normal pump-ups the bike can be left standing up (unless the tire is completely flat again).