New biker here. bought this bike used, gone on a few rides and have pumped the tires already before. The most recent time though I couldn’t get the pump on the back tires valve and I’ve fully deflated it and am unable to reflate it. the valve is very lose and honestly i’m too new for this and youtube isn’t helping me much. Any tips or comments?
by Professional_Value56
11 Comments
It looks like the valve stem has separated from the tube, you may have to pull the tire to see.
It’s kinda common for that to happen.
Most likely new tube time.
The valve stem screw is missing. Also it looks like the valve had separated from or torn the tube. Just replace the tube and make sure the screw on lock ring is fitted.
Contrary to what others are saying, what your video shows is normal for a deflated presta valve.
Presta valves don’t have springs like Schrader valves do, meaning they rely on a tightened nut for a seal, and therefore if the tube is totally flat, pushing the rod in and out requires little force. Similarly, pushing any tube’s valve into the rim requires little force if the tube is flat.
My guess is that you were fortunate the first time you inflated, and less fortunate the second time. Maybe you didn’t get the valve far enough into the pump head the second time. Maybe you got it into the pump head too far. Either can lead to air not entering the tube, and instead getting caught in the pump hose or escaping around the valve.
Indeed it isn’t but all the more reason here to have one!
Push from the tire side to be able to get the pump on without the valve stem pushing into the rim. But it does sound like the tube is damaged. Also, I’m assuming the valve stem is not threaded. Normally there would be a ring nut that tightens against the rim, although some tube valve stems are not threaded.
Looks ok to me. Lock the pump head on and pump to desired psi.
The problem is, with the tube 100% flat, you’re probably just pushing the valve stem down into the tire when you’re trying to push the pump head onto the valve. Normally there’s a threaded nut that keeps the valve stem in place to prevent this, or residual pressure in the tube can help do the same.
To get the pump head to properly attach, you could use some pliers to grab the base of the valve stem and keep it from pushing into the tire. Or even just push the valve stem sideways, so it binds up in the rim instead of moving down.
Put your thumb against the tire directly behind the valve stem and then push the pump head into the valve. Should lock in place just fine and inflate like normal. If you’re sure the pump is fully seated and it still won’t take air then you need a new tube.
man, the comments in here are absolutely wild for a sub called “bike wrench”.
There’s no nut for this valve (some tubes, not all, have a threaded valve head that locks onto the wheel and holds the tube in place, but not this one)… this is how this tube comes from the factory and it’s extremely common on road tubes…it’s common on larger tubes as well, so …
Pinch the valve through the tire, and hold the valve up through the rim as you attach the valve head and inflate… that’s it.
As you inflate the tire pressure will hold the valve against the wheel and you won’t have any problems topping off as long as you have inflation pressure.
I just had this problem. I get your frustration.
If you can’t try a different pump, but you do have a third hand (helper) do this: one person holds the stem and gently puts the nozzle of the bike pump on it, the other person pumps. It didn’t take much for me to get a seal between the stem and nozzle. It also didn’t take much pressure to inflate the tube enough to keep the stem pushed out.
After that incident, I went out and bought a CO2 cartridge inflator. I deliberately emptied my tube and discovered that the cartridge blasts out air so fast that I don’t need a helper.
Anyway, it turned out to be an actual leak so I replaced my tube with one that has a nut on the stem.
Push on the tyre tread to in turn push the valve further out of the rim and keep pushing whilst you put the pump on.
There’s no valve lockring or threads for one, so it may be a TPU tube in there.