rachel120

I feel like an idiot, but how do you inflate a bicycle tire?

Last night riding home it felt like I hit a small rock. But the tire was fine the rest of the trip. This morning the tire seemed fine so I rode it to work, a 3 mile trip. I got out of work, walked to where my bike was chained and the tire was flat as a pancake. So apparently that rock really did do some damage.

Since it took an entire day to deflate, I figured the leak had to be tiny. I went back in, got a little tire pump and nothing. I had thought it would be like inflating a car tire when I attached the nozzle. I called for a ride, and continued pumping with the little pump, total of one hour, no pressure at all. My ride took me and the bike to a gas station with a digital air pump, and using that on the tire as if it were a car tire, still nothing, the air pump there couldn't get it to rise as much as a pound.

I did my best to check the inner tube for a puncture, never found one, but light was starting to fail when I got outside and I'm new enough to all this that I probably wouldn't see it if it wasn't obvious. I can't figure out how to get it off the frame of the bike, so I can't partially inflate it and throw it in a bathtub and look for bubbles. Here's a picture of the valve stem (or whatever they call it on bicycles); how do I get air into it?

csport

What is the black substance around the valve in the picture? Is it the rubber from the inner tube? Then it may be ruined, and you need a new one. You will need to take the wheel off and replace the inner tube. See for example this article by Sheldon Brown: https://www.sheldonbrown.com/flats.html

From what you are saying it appears there is a huge damage to the tube somewhere so that the air does not stay there at all.

AndreyT

So, what exactly happened when you tried to inflate it with a gas station compressor? Did the air just flow through the tire? With such a powerful pump as the ones typically used at gas stations, it would be pretty easy to see (and hear) where the air leaked from the tire.

rachel120

The black substance came from the gas station air pump. It was all shiny when I took the cover off outside of work.

What exactly happened is this - that air pump is digital, you set the pressure you want and put the nozzle on the tire. It'll blow air in for a bit, then take a break and measure pressure. The air went in but every time it took a break, the pressure read zero. I do have hearing loss so teeny little sounds are not my forte, but that machine is really noisy when the motor runs and the sounds of filling didn't seem unusual, though as always the motor kinda overpowers over the filling sound. The tire has an inner tube that actually holds the air, it didn't puff up in the slightest while I was trying to put air in.

csport, if the damage is so great that air is going out as fast as it goes in, then why did the tire seem fine all the way home last night and all the way to work today? If that bad, wouldn't the tire have deflated shortly after I hit the rock?

Bill Kapaun

Are you pushing the valve from the tread side (with your thumb) to keep the stem protruding?
I have a hunch you're just pushing the valve into the rim.

csport

I thought it had got some extra damage during inflation. The other possible cause is this:

dabac

Riding an underinflated tire can cause the tire to creep on the rim, dragging the tube with it.
While less common on Schräder (car-type) valves, this tire creep can pull hard enough to tear valves from tubes.
My guess would be either that, or you didn't manage to get the nozzle to engage properly.

JonathanGennick 

Have you been able to get the wheel off and the tube out yet? Then you can swap in a fresh tube, and sort out whether to patch the old one while still being able to ride the bike.

rachel120

Yeah I did push from the opposite side, I noticed right away the valve would push into the rim.

The tire pressure felt like the back tire when I squeezed it yesterday morning, concerned about overnight leakage. I don't think I damaged it in the parking lot since I stood near the bike for a bit to talk to someone and the tire looked fine after the conversation.

My husband is wondering if someone could have sabotaged it while I was at work. How likely is that?

I haven't tried taking the tire off yet. I will get a spare tube first. Last night I noticed work sells two types, standard and self sealing. Which would you all recommend? The brand is Schwinn.

Crankycrank

rachel120, you can always find good videos on YouTube or Park Tool.com, etc., to show you how to do most anything on your bike including filling your tube, removing the wheel from the frame, removing the tire, patching the tube etc. Of course here is a great place to ask too but sometimes a good video really helps. You should learn how to replace/patch a tube and carry a spare tube, patch kit, tire levers and a pump because flats are inevitable. It's good to practice at home first too before you find yourself out on the road with a flat and it does take some practice. Always best to be a self sufficient mechanic with your bike. Some bike shops offer free basic maintenance classes or offer them for a fee. Also bike Co-Op's are good if you have one near you and as mentioned plenty of videos available to help you out. Self-sealing tubes can help in some situations where you get a very small puncture but they have a goo inside that makes it very difficult to get a patch to stick if the goo doesn't seal the hole. Try one and see if it works for you.

Jon T

Maybe try tire liners and thorn resistant tubes?
Jon

rachel120

I think it was a manufacturing flaw, not a rock, not sabotage. There was a tiny split on a seam that had been heat treated together and the seam split even more when I grabbed that general area and brought it close to see better and rolled the tube a bit with my thumbs.

I'm glad I did buy a replacement tube before starting. I'm not bothering to patch this, unless I decide to practice. I don't trust that seam to not split further, even after the patch is attached.

Bill Kapaun

If you practice on it, poke a hole in it and patch that.
Trying to patch a seam split would be a waste of patches. You want a successful result from your "practice".

rachel120

Could under-inflation have caused it? I'm completely bike dumb so I didn't think to check the tire pressure immediately after purchase. When I got it inflated to what the pump said was the proper PSI (I can't find my little gauge in my car to verify, I'm buying a new one before trying the bike) the tire was hard as a rock. When I squeezed the back tire, it could be squeezed a bit and as I recall the front tire was the same way.

rachel120

The back tire was under-inflated. The pressure gauge matched the pump's gauge for the final result. Since I inflated it prior to getting the pen gauge I can't be sure how low but I think a lot, maybe even 20-25 psi low.

I need to look and see if the Dummies series has one for bicycles.