Ronius_Maximus

Hello all, I was on my way to meet my wife for lunch today and I have unbelievably destroyed 3 tire tubes today, 2 kenda and 1 forte 700x28-32c tubes. The tires I have are continental gatorskins in 700x28. To describe myself im a bit less than 250 pounds and 6'4" tall. As I was preparing my bike this morning I noticed that my rear tire was flat so The first thing I did was uninstall the rear tire and tube. To my discovery, the area where the presta valve is connected to the whole innertube, incurred a hole right around the edges of the valve. Okay, so I put in another kenda innertube and pumped up the tire. As i was nearing 100psi, i hear air start to come out of the presta valve. So, again, I unmount the tire and notice that the same problem arises - the area around the presta valve where it connects to the innertube has started to separate AGAIN. Okay, so I was going to call it a day until I found one last innertube, a forte 700x28-32 in my parts box. I install that tube and everything checks out aye-okay. I get on my road bike and embark on a 11 mile journey to my wife's work to meet her for lunch. As I approach 7.54 miles, I thought a turbo'd WRX was driving by me and showing off its turbo but no, that was the sound of my innertube going out AGAIN. So I take a look at the tube and again, its the same problem that im not even going to type since ive already fat-fingered several words using my iphone 4s to type this all out any particular reason someone can give for this? Is it the lock ring on the presta? I kept it somewhat snug but more on the loose end during the 3rd tube today. Any help or input is appreciated, thanks!

rearviewbeer

Sounds as though there is something cutting the tube around where the hole is. Make sure to feel around it to see if there is something sharp that is cutting it. Once you find it you will want to file it down so it does not continue to happen. Either that or you got 3 crappy tubes in a row - highly unlikely though.

TrojanHorse

I remove the lock ring on the presta valve on my bike. It's not necessary for anything.

You are either damaging the valve when you inflate the tire *or* there's something there that's damaging your tubes. RUmmage around there with your finger (be careful) and see if you can identify any sharp edges.

Bill Kapaun

Is the valve hole Schraeder diameter?

Buck_O

I dont mean to sound insulting when i say this...but...

How many tubes have you changed in your life?

Do you slightly inflate the tube before stretching it onto the rim?

Are you installing the valve first and then working your way around?

How are you managing the tire on the rim of the wheel while you are inserting the inner tube?

When you go to reseat the tire to the rim, are you starting at the valve side, or finishing on the valve side?



Again, not trying to be condescending, just trying to get a better idea of what youre doing, and trying to find where things are going all pear shaped.

bigfred 

Check the rim for burs.

But, more likely, lose the lock nut. And, are you using a floor pump to inflate before each ride at home? Or, a frame pump? A rigid frame pump without the head and valve properly supported can be pretty tough on a tube.

r32nj

I've always wondered about this. I see a lot of people recommend NOT to use them. Without them I've wondered how much stress is put on the tube when connecting and disconnecting a floor pump (as the valve moves around more).

Any thoughts?

Wolfwerx

Maybe not related to your problem (I would definitely go over the inside of your rim to check for burrs and such), but I have had extraordinarily bad luck with Kenda tubes. The last time I had used them, I bought 6 tubes and all of them have failed by the valve stem.

indyfabz

Another possible cause is installing the tube in such a way that the valve is not straight but rather angles to one side.

I, too, am wondering if your rims are drilled for Schraeder valves.

Wolfwerx

Good idea... I see this all the time.

magohn

I would guess its a foreign object still left in the tire. Usually the most obvious reason is the correct reason

I must be very lucky. I have close to 4000 miles on my 2010 Roubaix (stock wheels with replaced cheapo tires) and can honestly count on one hand the number of flats I have had. I started riding the Roubaix at 320 lbs (now down to 280lbs) but ride VERY defensively. I avoid potholes, ridges and ride out of the saddle over rough road. I even rode 204 miles over 2 days and not a single flat. Tubes I have replaced are from any cheap source, even Walmart. I ALWAYS pre-check my tire pressure on any ride over 5 miles.

Ronius_Maximus

Thank you all very much for the replies. In regards to how i install them, i usually start with the valve area and work my way around. I have been using a frame pump to pump them which may be stressing out the valve from the tube. The rim is a magic cross pro and is for presta. I have yet to check around the vavle hole of the rim but im pretty sure theres nothing there that is out of the. Orm in regards to slicing it but aimcould be very wrong.

TrojanHorse

Highly likely that this is happening. Workarounds include getting a nice floor pump (they are WAY easier to use but less portable of course) or getting a frame pump with a little hose that connects to the valve. Lezyne microdrive for one, or I think the topeak road morph does as well.

Mark Stone

Another thing to think about is the accuracy of you pressure gauge - sometimes they go out of whack and we think we're approaching 100psi when we're actually 130 or 140. In my experience overinflated Prestas fail at the stem like you describe. I speak from experience - -

dramiscram

He dared!

Black wallnut 

If the lockring is a problem then I must be pretty lucky. I've not had a flat yet caused by that. My last flat was over 2000 miles ago! That was in February of this year. Over-inflation or stressing the tube/ stem junction while adding air seem more likely to me.

Change brands of tubes, check the inside of the rim where the stem passes through, buy and use a good floor pump saving the frame pump for when you need it out on the road. You might even give some thought into the CO2 inflators for out on the road, very small chance of stressing the stem to tube junction with those.

TrojanHorse

Doomed!

Mark Stone

+1 on the Road Morph. Awesome little pump - stand, hose, handle, it's like a tiny floor pump.

jesspal

Check the rim.

Wolfwerx

Agreed. I bought one based on the love BF gives it, and I am quite happy with it.

psalm

What kind of rim tape do you have? If it's that cheap plastic stuff, sometimes the edges can fray. If it is the cheap plastic stuff, get some better tape. Preferably the cloth type.