I'mnotdeadyet

First time about 5 miles out. Second time 3 miles out. Today, 6 miles out. I first start to hear a regular rubbing sound. Then Ka-Boom! There's about 6 inches of the tire off the rim, and the tube has made its way through and explodes. The first 2 times, it seemed to happen right around the value stem, and I thought I just hadn't checked the seating after I had pumped up the tire to 100psi ( its max of 105 psi.) Today, not in that area. I can't say if it happens on the same side all the time. I have a Panaracer T Serv 28c on a Alex DM21 rim. No problems up front with the same set up. I pulled the rim, and checked for flat spots, or out of true. All in all, pretty good. I will change the funky OE heat shrink rim tape tomorrow, which does go up the side wall in places, but not into the bead. I've been on rides in between, and even a 64 miler, so it doesn't happen every ride. The only thing I could think is that the bead on the tire in bad or stretched. Luckily I carry extra tube, CO2 and a pump. Its happened with both my different stokers. And happens going slowly and luckily on the rear only.
What do you guys think? New tire?
Thanks
INDY

tford

Get yourself a set of Conti Gatorskins.

TandemGeek

Definitely consider a new set of tires and you may also want to replace the OE rim strip with some good old fasion Velox tape while you're in there.

Also, make sure you do a good job of setting your tire bead and centering your tire as you inflate it when you put the new tire on the bike... belt and suspenders, if you will, just to make sure there isn't a rim bead issue. If it seems like a certain part of the tire bead wants to lift in the same place.. and that place coincides with the same place where your past 3 tire blow-offs occured, the rim may be the problem.

cornucopia72

It sounds like your rear tire has a rotten sidewall. Replace it or both

I'mnotdeadyet

Thanks guys.
I was going out tonight to get some good velux rim strips.
I did watch the inflation and the popping of the bead when I was inflating the tire, but I'll double check. I also checked the rim quite closely, but that doesn't seem to be it. The ID of the rim is 17.5mm. Maybe a little wide for a 28c tire?
I have been inflating it to 100, and the tire's max is 105, so that shouldn't be a problem.....but maybe its like you say, the tire.......

SDS

It might be the tire, or as noted above, a deficiency of the rim (check for the prominent beads on the inside edges of the rim at the top), or it might be a problem with assembly. You can't have any tube visible either under or outside the bead of the tire, before inflation. With the tire fully on the rim, I always push the valve stem into the rim to get the tube well into the tire, and then I push the tire down onto the rim at the valve stem to get the tire beads well into the rim, and then I pull the stem back to trap the tire beads and install the valve nut, if equipped.

I always get one tire bead onto the rim, push the tire to the opposite rim wall, and then insert a tube WITH NO AIR IN IT, rolled flat with no twists and the valve closed, and stuff that to the tire wall pushed to the opposite rim wall, and only then seat the other tire bead onto the rim. Then I go all the way around the rim, pulling the last bead seated toward the opposite rim wall, looking for inner tube. Any observed portion of tube has to be properly inserted into the tire by one means or another, and only then will I inflate the tire, perhaps once only a little, then deflated, then fully inflated. The minimal inflation and deflation might allow any trapped tube to escape from under the bead to inside the tire.

A lot of people say a partially inflated tube will not get trapped under the tire bead when inserted into the tire because of its round shape. I have had more success with completely deflated tubes that have NO AIR in them.

zonatandem

We do very slightly inflate tube before inserting it into tire. Then totally deflate it and put tire on rim. Check for no tube protrusion. Slightly inflate (may 20 lbs.) then deflate completely. Double check that tube is all inside tire. Now inflate fully and recheck that tire is seated all the way around without any tube showing.
Just our way of doing it for over 3 decades.

cornucopia72

We inflate the tube by mouth before inserting it into tire. Start working the tire in and leaving the area near the stem for last. Then totally deflate the tube and finish putting the tire in, all by hand. Slightly inflate (maybe 10 lbs.). Go around the tire checking for proper seat on both sides every 8 inches or so. Inflate to full pressure.

t4mv

I think it's your rear tire bead going, too; I had a brand new pair of Vittorias on some Concaves and the rear tire kept wanting to blowing off the rim (right in the garage, never mind miles down the road), always in the same spot, so I figured it was damaged in shipping since it had to be folded to ship in a box. The front tire never has a problem. If Gatorskins fit, I'd opt for those, too.

joe@vwvortex

You need tubulars! :-)