Pumper or pumpee?

Deadlast01 said:

I started cycling a few months ago, and nothing has comfounded me more than bike tubes.

I have a Blackburn TrackPump Sport 2 pump, and I inflate my tires to 110 psi.

The first problem I was having was that, after inflating the tire to the proper psi, I couldn't remove the pump nozzle from the presta valve. Despite my best efforts, I managed to separate the base of the stem from the tube. This happened with three tubes.

Today, I properly inflated the tire to 110 psi and successfully removed it from the stem only to have the tube explode 2 minutes later. I ckecked the rim and tire for some clue, but nothing to suggest the cause. I tried another tube, and the same thing happened. Needless to say I'm a little fed up!

These two distinctly different problems are either caused by (a) a defective pressure gauge on my pump or (b) the fact that I don't know what I'm doing.

Any suggestions are appreciated!

There are a lot of things that could be going on here:

- you could be mounting the tire and tube incorrectly
- you may have a defective pump
- as you say, you might be doing something incorrectly

The best way to learn these things is to have someone show you how to do it correctly. Either find an experienced cyclist to help you or go on down to your local shop and explain what your problems are. Bring your pump and your wheel and have them show you how to mount the new tube and tire and use the pump properly. Be honest and let them know you've had problems and they'll likely be happy to show you the correct method. If your pump is bad, then they should sort that out promptly. Spending a few bucks and buying a couple of new tubes will make it easier for a shop to justify giving you a lesson.

Basic tasks like pumping up a tire and fixing a flat are not necessarily intuitive and there is no shame in asking for help from someone who knows. Learning these tasks is really important or you will be in for some very long walks pushing your bike. Take the time and effort to learn to do it right. Best luck!

Ain't dat aggrivating.

I'll discuss the second problem first. You have probably pinched the tube somewhere under the tire bead. When you do that, the air pressure tries to push the tire bead off of the rim and sometimes, as you have discovered, succeeds. The solution is to put just enough air in the inner tube to give it shape before attempting to install the tire. If you have any doubts, carefully push the tire beads in toward the centerline of the rim and visually inspect the tire all of the way around on both sides to be sure that the entire inner tube is safely contained within the tire caseing.

Tire chucks should fit just snugly onto the valve stem when the chuck lever is in the release position. If your's fits too tight, you can usually make it fit a bit looser by unscrewing the part that holds the gasket in the valve head.

Both issues will get much easier with experience.

I agree with this statement. You have probably pinched the tube. I have done it many times. Now I always put tube in the tire, on the rim, then check by pinching the tire to make sure the tube is not outside the bead (caught between the tire and the rim). Put in a couple of pumps of air, then check the tube/tire again. Takes a little more time, but a don't get any pinch flats when I do this.

Second issue, the pump. I have two pumps, one pump is compact for for the frame. The other pump is a nice shop/floor pump. Sounds like you are using the compact pump for all of your pumping. It is a whole lot easier to use the floor pump, and only use the compact when you have road flats. When you use the floor pump, because of the hose, you are not constantly moving the valve stem, which is causing the breakage.

Retro Grouch said:

Ain't dat aggrivating.

I'll discuss the second problem first. You have probably pinched the tube somewhere under the tire bead. When you do that, the air pressure tries to push the tire bead off of the rim and sometimes, as you have discovered, succeeds. The solution is to put just enough air in the inner tube to give it shape before attempting to install the tire. If you have any doubts, carefully push the tire beads in toward the centerline of the rim and visually inspect the tire all of the way around on both sides to be sure that the entire inner tube is safely contained within the tire caseing.

Tire chucks should fit just snugly onto the valve stem when the chuck lever is in the release position. If your's fits too tight, you can usually make it fit a bit looser by unscrewing the part that holds the gasket in the valve head.

Both issues will get much easier with experience.

You've probably pinched the tube, and often you can visually see when you do this but sometimes you can't - after the tube explodes, it may then "tuck itself back into the tire," so you won't be able to tell that it was indeed sticking out. I've had the best success putting the tube inside the TIRE first (not inside the rim) and then putting the valve through the hole in the rim - inflating it just a bit to give the tire shape - mounting one side of the tire inside the rim, mounting the other side of the tire inside the rim, then finally inflating the tire up to pressure. I know, that sounds simple and straightforward, but it really is not. Describing it is a bit tricky, so it may be good to have an experienced person show you. There are also some excellent diagrammed articles online on how to change a flat, which are easy to find.

I've been bedeviled by pump gaskets since I started riding 2 years ago.

First pump head was too tight and the gasket got ground down by moving it over threaded presta valves until it wouldn't stay on without somebody holding it (my wife. She loved it).

I replaced the pump head a couple of weeks ago and expected all to function well. I promptly ripped the stem out as you describe. After dividing by 0, I applied my brain and I finally solved the problem.

I just put a small amount of lithium grease in the presta valve hole and spread it around with a toothpick. End of problem. The gasket seals tightly enough to stay on, comes off when requested and doesn't get ground up by unnecessary friction. :p