5

I have a new bike (been less than a month since it was purchased) and has been ridden for about 600km (375 miles) on bad city roads.

What may have caused this bend of the valve pin? Is it possible for me to be fixing it right at home with a very basic tool kit that I have?

Should I try bending it back to the middle, or is it best to take it to a shop and have someone fix it for me?

I'd also like to know what may have caused the bend because the bike hasn't been in any crashes whatsoever, or even gone over a pothole that I would consider mighty or particularly worth noting.

enter image description here

3
  • What chance it was that way from factory?
    – Caius Jard
    Nov 9 '20 at 16:46
  • It wasn't, I can assure you that since the tyres have been inflated multiple times..
    – Timon
    Nov 10 '20 at 3:48
  • Is the pump valve head attachment in good condition? Schrader valve pins are often pressed down by a "finger" in the pump head that moves when you move the locking lever that seals the head to the valve stem. If that finger is chewed up, might it have bent the pin?
    – Caius Jard
    Nov 10 '20 at 13:36
6

You have a Schrader valve. The pin on the valve core has been bent or the core is cross threaded in the stem - the picture is a little blurry.
You can remove the core by unscrewing it from the stem. There is a special tool for that, sometimes skinny needle nose pliers can be used.

Here are the options I can think of:

  • If the pin is bent or the threads on the valve core are ruined you'll need a new valve core. The shops I've worked at would replace it for you for free.
  • If the core is cross threaded you may be able to remove it and thread it back in straight.
  • If the threads inside the valve stem are ruined you'll need a new tube.

Hard to say what caused the damage but it's probably related to something getting cross wise during inflation. A bent valve core pin is unrelated to road types or number of miles.

enter image description here

4
  • I'm fairly tool-obsessive about what I carry on the bike, but even I don't carry a core remover tool. I do carry minimum of two tubes and stickers, and these are a good addition to the home toolkit.
    – Criggie
    Nov 8 '20 at 18:56
  • 2
    @Criggie The #3 spoke wrench fits on a presta valve core.
    – MaplePanda
    Nov 8 '20 at 20:18
  • 2
    @Criggie - It's very easy to carry a valve cap with a core remover built into it. Nov 8 '20 at 23:33
  • There are two-sided core-tools that combine Schrader and presta core-removers and that are easier to handle, from Park and others. A mini pump that I recently bought has a presta core-remover built in the hose.
    – Carel
    Nov 9 '20 at 9:16
5

Just use one of these as a valve cap. You can probably remove the dodgy core with it, and either bend it straight or replace with one from a spare tube.

enter image description here

5
  • I have a tool similar to those valve caps by Schwalbe (bike24.com/p2142139.html) and it’s quite heavy. Isn’t screwing such a mass to the valve cap going to unbalance the whole wheel noticeably?
    – Michael
    Nov 9 '20 at 8:25
  • Since the cores are identical to those used in cars, you may also be able to buy them at service stations, at car parts dealers or motorbike dealers if there is no LBS in the neighbourhood.
    – Carel
    Nov 9 '20 at 9:10
  • @Michael: Cycle wheels due to the larger diameter and lower speed turn at a lower RPM than car wheels, so the imbalance is probably not noticeable.
    – Carel
    Nov 9 '20 at 9:13
  • @Michael - They're not that heavy. Nov 9 '20 at 12:48
  • @DanielRHicks: Just looked it up, it’s 4g.
    – Michael
    Nov 9 '20 at 13:10
4

It looks like the valve core is missing. If it is just bent, then I cannot see it in the picture.

If it is indeed missing, then it might have been unscrewed and then it popped out due to the pressure and jumped somewhere.

If it is there, you can unscrew the core follow as if it was missing.

You can buy a new valve core

enter image description here

(photo https://commons.wikimedia.org/wiki/File:Ventil_3.jpg Creative Commons)

and install it to your valve, but frankly, I would just buy a new inner tube.

If it is bent, it most likely happened when inserting the pump. One has to be a bit careful when doing it, the pump pushes on the pin and it should be done in the straight direction in order not to damage the valve.

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