mrund3rd09

So yesterday, I had to walk home because my front tire was flat. I ride a vintage road bike and my front uses schrader, btw. It turns out, the valve was partially severed from the tube. So I switched it out with my backup, made sure the valve was pointing straight, and everything looked normal. And this morning, the front tire was dead flat again. I didn't have time to check what was wrong with it, but I suspect that the valve got severed again, because I checked for leaks on the tube the night before. When pumped up, the tube is uneven with some places thicker than others, but I didn't think much of it.

Am I putting too much pressure into my tires? I try to get it around 100, which I assume drops to ~90 when I remove the pump attachment. One thing I noticed was that if I pull too hard on the valve when I try to detach the pump, the valve would start sticking out more, with some of the rubber tube dragging out at the base of the valve. This happens almost all the time to me with my bike/pump. At that point, I would just release the air and start pump all over again.

Do I need a new pump? Am I doing something wrong?

ahsposo 

Let's make sure we are on the same page.

zaqwert6

100psi into a schrader?

Retro Grouch 

A schrader valve will handle 100 psi with ease.

It sounds to me like the OP is tearing the valve stem while removing his pump chuck.

mrund3rd09

I try to be as gentle as I can, believe me. I would shake that thing from side to side in an oscillating motion until it comes off. Sometimes, it would just not come off, and when I pull harder, the valve drags part of the tube out with it, and then I have to let the air out and do it over.

SteamingAlong

Could be the brand of tube you're using too. Sun tubes SUCK for instance. Their valves are garbage.

Retro Grouch 

Are you sure that you're using your pump chuck right? Some you pull the lever out to release the chuck and on some you push it in to release the chuck. Look into the end of the chuck and see if it seems to get bigger or smaller when you pull the lever out.

zaqwert6

Well obviously the valve itself is.

I just don't run into too many schrader valved HP bike tires myself.

ahsposo 

Can you not hold the stem while pulling on the chuck?

I was initially confused. To me the valve is the little springy thing that is inside the stem on a schrader type. I couldn't see how you damaging that.

On my hybrid that has schrader type valves I've started buying longer stems so I can grab them while removing the chuck because I too have ripped stems right off the tube.

mrund3rd09

Right, I'm switching to presta valves. I just went to the store to buy the rim adapter. I figure because the diameter of the valve is large, and the width of the tube is small, it's a lot easier to pull the tube out through the larger hole in the rim. I don't think that will be the case with presta valves. Besides, presta valves are very well built at the stem, so I don't have to worry about it again... someone mentioned that sun tubes suck? why? I'm on amazon purchasing a thorn proof tube, and the cheapest ones are avenir and sunlite

alhedges

Schwalbe schraeder tubes are built like presta tubes - metal valves threaded down to the rim where there's a locknut. They are the only tubes I'll buy.

mrund3rd09

the thing I don't like about schrader is the rubber part of the stem is exposed and vulnerable. If that part gets a leak, then the tube is done because the patch won't do a very good job. I'll double check, but I think I got my tube from the local bike store, which supposedly sells good stuff. Anyways, I'm switching to presta. I think the valves are more suitible for road bikes for their thinner neck and their sturdy construction at the valve stem. Plus, I don't think I will have to worry about yanking the pump clamp off of the valve anymore.

Retro Grouch 

Don't bet the rent money. There have been dozens of threads from posters who have torn presta tubes at the base of the valve stem.

JanMM

Tires don't care what kind of valve the tube has.

zaqwert6

Whats with you guys? Just trying to be sure we know what where talking about.

Sheesh. Any chance YOU actually offering some help instead of being a smart a$$?

Yea, didn't think so.

Retro Grouch 

So explain. How does "100psi into a schrader?" help the OP resolve his tearing his tube at the valve stem problem?

BlazingPedals

I'd be glad to help -- if you weren't the better part of a thousand miles away. The problem is, without looking at what you've got, it's hard to say what's going on. You could have a burr on your rim, at the valve stem hole. You say it's a vintage bike - is it steel rims? A pinched tube is a possibility for the second flat; but without inspecting I can't tell. Schrader valve stems are pretty sturdy; I doubt that 'normal' handling will rip one out in a day. Unless the tube is old and the rubber is failing.

JanMM's statement was true. Don't blame the type of valve; something else is going on.

bkaapcke

When you change out the tube, check the valve stem hole in the rim. Are the edges smooth and free of burs? If nor, fix this before you complete the repair. If your rims were presta and someone drilled them out for schrader, the hole could have sharp edges. And alhedges is right. Schwalbe schrader tubes are the best. bk

no1mad 

1. What's the rating on the tire's sidewall?
2. Possibly. What type of pump are you using? Floor pump, one of those rigid sticks, or something like the Topeak Road Morph?

mrund3rd09

1. 100 psi, but I've been told by people on here that's not really an issue
2. walmart pump that has both presta and schrader ends.

you might be right. I bought the bike from an old man who rides for fun. He might have gotten the hole drilled. But that shouldn't be an issue anymore, considering I just put in presta fittings that have pretty blunt edges. I also like how the stem is like a screw that you can lock into place on the rim, so the tube never slides.

My 2nd flat was due to a poor patch job, not a valve problem. I could see an air pocket collecting in the middle of the patch, where the hole was. The tube itself didn't look like it was in great shape either.

Because I hate getting flats, I want to get a thorn resistant tube - one of those thick ones. Does anyone have a good suggestion for a presta valve 27x1-1/4 tube that's well built and cheap as well?

Retro Grouch 

Go gentle with the presta valve nuts. I used to have a delightful Chinese bike mechanic who called them "the work of the devil". If you take a corner too hard, the tire will deform and the tube won't be able to conform with the tire. When that happens it'll tear the tube at the base of the valve stem. Personally, I throw those little valve stem nuts away. I don't want any workings of the devil on my bike.

DX-MAN

Retro, about those little 'works of the devil'...my experience is, pump the tire up to max or near it (60psi is my benchmark, 26x2.1 tires), SNUG the nut, and when the pressure goes down to where you like it, you'll have the flex you need. Has worked for me for 7+ years.

mrund3rd09

interesting. I'll loosen the nut a little. I never really corner too hard. I never have ever since I tried to corner at a 90 degree angle on a flat tire when I was in 4th grade, with sand on the pavement... that was the last time I cornered anything.

Would that be why schrader valves tear at the base stem if the rim hole is too sharp?

Retro Grouch 

I don't know. That's a problem that I've never encountered. I'm wondering is somebody drilled out the valve hole for schrader valves and didn't de-burr the hole.