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Old 09-22-11, 08:55 AM   #1
chandltp
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buldge on schrader valve stem

So I noticed the other day that the valve stem on my front tire wasn't coming straight out from the rim anymore, but leaning to one side. I then noticed a small air pocket at the base of the stem where it comes through the rim. Am I looking at an imminent failure, or should I continue to ride on this?
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Old 09-22-11, 09:00 AM   #2
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That will fail sooner rather than later. Install a new tube and be done with it.
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Old 09-22-11, 09:53 AM   #3
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Originally Posted by chandltp View Post
So I noticed the other day that the valve stem on my front tire wasn't coming straight out from the rim anymore, but leaning to one side. I then noticed a small air pocket at the base of the stem where it comes through the rim. Am I looking at an imminent failure, or should I continue to ride on this?
For the sake of the price of a beer, I'd rather not risk eating the tarmac. Front blowouts suck.
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Old 09-22-11, 10:15 AM   #4
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You might get by simply pulling the tire, inspecting the tube (inflate outside the tire and look for any local bulges) and remounting it correctly, with the valve properly seated and straight.

Many tubes are failing these days because the valve isn't properly molded (not a defect, a poor design) into the tube causing a weak area at the base. I routinely punch a hole out of a patch and fit it to the base of the valve as added reinforcement.
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Old 09-22-11, 10:29 AM   #5
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Thanks for the feedback.. I was pretty sure it was best to replace it. The LBS sold me too small of a tube telling me it would be easier to mount.. I don't know if this contributed to the failure. It was a 700 X 28 max in a 700 X 35.
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Old 09-22-11, 10:39 AM   #6
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Thanks for the feedback.. I was pretty sure it was best to replace it. The LBS sold me too small of a tube telling me it would be easier to mount.. I don't know if this contributed to the failure. It was a 700 X 28 max in a 700 X 35.
A bigger tube might help, but this had nothing to do with your problem. the leaning valve was caused by improper mounting and seating, or the tire creeping around the rim, which often happens if you ride somewhat under-inflated.

That coupled with the weak valve I described earlier is the cause. When you mount the new tube, be sure to keep the valve straight, and the tire seated.
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Old 09-22-11, 12:07 PM   #7
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A bigger tube might help, but this had nothing to do with your problem. the leaning valve was caused by improper mounting and seating, or the tire creeping around the rim, which often happens if you ride somewhat under-inflated.

That coupled with the weak valve I described earlier is the cause. When you mount the new tube, be sure to keep the valve straight, and the tire seated.
It's leaning to the side so I don't think it's related to tire inflation in any way, and I check my tire often enough that I've never ridden with it under-inflated.

It was fine for the first 500 miles or so, and then I noticed it was leaning to the side. I did notice the stem was pretty tight in the hole, so maybe I didn't get it all the way through. I'll be more careful when I replace it.
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Old 09-22-11, 12:23 PM   #8
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...

It was fine for the first 500 miles or so, and then I noticed it was leaning to the side. I did notice the stem was pretty tight in the hole, so maybe I didn't get it all the way through. I'll be more careful when I replace it.
Buy your new tube so you have it.

Before pulling this one out, deflate the tire completely. Push the valve deeper into the tire, then make push the tire beads down to make sure they're seated, then gently ease or wiggle the valve back out until you feel it bottom before re-inflating. If it was only a minor seating or fitting problem you can save the new tube for next time.

If the tube turns out to be a problem, or the valve breaks off with your handling, you've only lost a minute, and can go ahead and replace it.
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