Proper way to store bike tires...and did I kill these?
 

Today I put on a set of Contis that I had taken off another one of my bikes last summer and they both had bad "humps" (or maybe flat spots) in them. I knew they where fine when I took them off the other bike last year, so I am wondering what happened to them in between.

They were stored in the garage standing up, leaned against a wall. They are wire beaded. Looking back on it now, I see how this could alter the shape of the tire, but I figured the pressure would straighten them back out after remounting them. It did seem like they got a lot better after 25 (bumpy) miles on the bike. Will they continue to even out, or should I toss them and get another pair?

Also, I do have a pair of folding bead tires. How should these be stored? The wire bead tires are within 1000 miles or so of death anyways, but the folding beads only have about 100 miles on them, so I would hate to screw up that pair too.

A lot of times, apparent flat spots are just installation issues when the bead isn't fully seated on the rim. You can check for this by inspecting the tire/rim junction while slowly turning the wheel. If it's not this, then the tire should even out after a short ride, assuming you stored it correctly.

Correct storage of unused tires doesn't really have position as a factor. The critical issues are temperature and environmental pollutants. Tires are made from organic material and they should be stored in a cool, dry place, away from sunlight (UV) and pollutants that are detrimental to rubber, such as ozone that can be created by the stereotypical example of electric motors from refrigerators. Tires will naturally degrade, but if you store it well, it should still be serviceable after many years. I have tires that are more than 10 years old that look and ride fine, for example.

I think you need to remount them straight.
Is the "bump" by the valve stem?

Sometimes tires stored flat take a set, especially if the sidewalls are a bit dried out. Car tires do the same thing. Once they're inflated and ridden the constant flexing works the set back out, and it won't be long before all memory of the flat spot is gone.

BTW- if the tire isn't round yet, riding with slightly lower pressure massages out the set faster.

Thanks for the replies. I will check the seating again tomorrow, but I am pretty good at doing the partial inflate/check bead/fully inflate as I air up newly mounted tires.

I stuff mine inside a plastic garbage bag and tie it closed to minimize air circulation (which might include ozone and other harmful pollutants. Keep the bag in an indoor closet so there aren't any extreme temperatures. But I've never paid any attention to orientation or folds and they've always gone back on without any flat spots or bumps.

Ozone is your biggest enemy in long term storage. The anti ozonant chemical typically used in rubber is staining (so it cant be used in white or gum formulas) and semi expensive (compared to all the other ingredients of a tire) so it isnt typically used. Storing in an airtight container of some sort is best.

-Pete

Thanks for the info everyone! I checked the tire today and noticed it has a bit of a bulge on the side in the same spot the dip is, so I think its just an old dead tire. The back tire did seem to straighten out a lot, so I will keep keep that one, and trash this front tire. I did unmount, then remount the tire hoping it was something I did wrong, but it stayed the same.

I'm pretty fortunate. My wife lets me store our extra tires under the bed in the spare room.