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Keep pinching my tube.... Frustrating!!!
#1
So, I was commuting to school the other day and I got a flat about half way to school. I didn't really have time to change my tube as I was already late and had a test so.... I rode the rest of the way on my rim, I know, I know, anyway that is the background.

I have since inspected the wheel which seems to be in good shape, changed the rim tape and have subsequently pinched the last three tubes that I have installed. Do you guys think i need a bead jack? It is odd b/c normally i can just do it w/ my hands but haven't been able to w/ this particular tire recently, which by the way looks worn out. My friend also thinks it could have something to do w/ the new rim tape I put on. The rim tape isn't really deficient in any spots as I think it is a little wider than the groove that it fits in and there are no areas in the groove that aren't covered by the tape. Anyone have any suggestions? thanks
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#2
I don't know what half the distance to your school is, but you probably damaged the rim, and now a nice sharp piece of the rim is blowing the tubes. Check the inside and top of the sidewalls on the rim for shards/burrs/deformations/etc. to see if something is popping the tubes.

And I don't see how rim tape could cause a flat, unless it's REALLY thin, and the nipple heads are blowing the tube. Do yourself a favor, and save some money. Don't buy rim tape. Go to walmart, and buy some strapping tape. The kind with fiberglass strands running through it, like this one http://www.google.com/products/catalog?q=strapping+tape&cid=8354903117792036451&sa=image#p . It's better than any rim tape you'll ever use.
Dedicated scholar of bicycles
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#3
Also: check you have the air pressure correct. Too low pressure causes pinch flats.
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#4
The location of the hole in the tube should tell you what is popping it. If it is on the inner surface, it is probably the rim tape. But as long as the tape is covering the spokes, it's probably fine.

If the hole is on the side, more likely you are pinching the tube when you install. And if you're using a tire lever to install the tire, that ups the chances of pinching considerably. There are tricks to installing tight tires by hand, but hard to describe. What I can suggest is to put a little air in the tube first so it holds its shape. Put the tube in the tire first, then the tire on the rim. Be very careful not to get any of the tube under the lever if/when you put it on.

But first, check the whole rim for burrs and sharp spots. You can get away with riding on a flat without destroying the rim, but you almost always scratch it up some. There's probably some rough spots that are making it harder to install the tire and might pop the tube. You can probably sound them out.
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