Lump in my tire

[Keith A]

I recently put on a set of NOS Michelin PR3's that I had. Everything seemed fine after the first couple of rides, but I have noticed a lump/bulge in the front tire. I'm not sure if it was there the whole time or not, as it's only noticeable on smooth roads.

Should I be worried about this or is it going to spontaneously explode? I've had problems in the past with the PR3's, which is probably why these were sitting around unused.

[gasman]

On the sidewall or on the tread portion ?

Come to think of it I would be nervous either way and if you plan to keep it move it to the rear tire to avoid dental damage at the very least.

[buddybikes]

Sure you seated tire correctly?

[Saxon]

Same thing happened to me with a new Conti GP4000. My lump was in the center of the tread and hard to see unless looking directly at the side of the tire while rotating it. I didn't have any problems with it on the bike until hitting around 34 mph. Then the lump became a serious issue! I'd dump it (or return it).

I've had Michelin Pro 4's that quickly contorted to the side (kind of "S" shaped on the rim) after riding them for a few days. That's why I went over to Contis.

[tv_vt]

Is it a lump in the tire, or is it a crease or fold in the inner tube? Worth checking that first...

[sw3759]

same problem recently with half dozen nos PR3's and another pair of pro optimums.the sidewalls were kind of sticky from what I assume is an adhesive breakdown when I installed them and barely made it back home from the first ride.i had to release the pressure down to 30-40lbs the get the lumps to subside enough to roll thru the frame and fork.have nos PR2's and 4's and no issues just the 3's.

[Ralph]

Before making a final decision.....I would reinstall them, making sure tube is even all around, and tire is seated all around.

[tv_vt]

You guys are baby-powdering both the tube and inside of the tires before install, yes?

[Keith A]

same problem recently with half dozen nos PR3's and another pair of pro optimums.the sidewalls were kind of sticky from what I assume is an adhesive breakdown when I installed them and barely made it back home from the first ride.i had to release the pressure down to 30-40lbs the get the lumps to subside enough to roll thru the frame and fork.have nos PR2's and 4's and no issues just the 3's.This has been my exact experience with several of the PR3's. I ended up taking them both off and upon closer inspection, the sidewalls were just falling apart :( I still have some PR2's that I'm using, and I have had some PR3's that were okay...but I only got a hundred or so miles out of these. Obviously, they have some age on them, but they were stored inside and not exposed to any light.

Thanks to everyone for their input.

You guys are baby-powdering both the tube and inside of the tires before install, yes?I normally do.