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I bought a new, unused mini-pump from Ebay, here:

https://bit.ly/2HbbYRW

From the enlarged views, you can see that the pump works with both Presta and Schrader valves.

For two kid's bikes, I can only get the pump to fit one valve out of four. For the other three, I seem to be screwing forever, with no mating.

Here's some info.

  • I use the Schrader setting. So the valve end of the flexible extension is screwed fully in.
  • The pump fits my car (UK)
  • All caps fit easily on all bikes.
  • A cap from my car fits all valves on both bikes.
  • All the caps from the bikes fit my car.
  • All caps, including the car are countersunk. So roughly 4 pitches of thread are missing. This makes the cap self-centering, so it's easier to start the thread, even if the attitude is slightly incorrect. I think If the threads on the flexible extension had been countersunk, I might have succeeded.
  • The flexible extension is not as flexible as they were 50 years ago. Those extensions could easily form an "S" shape. There's not much space for my fingers (but more space than with a chuck). The reduced flexibility of the current extension means that it's difficult to angle the knurled end such that the axis of the knurling is inline with the axis of the valve. So the angle is offset by about 2 or 3 degrees, which is enough to prevent the threads from mating. I suppose a stronger guy with leather-tipped fingers might be able to do it.

I would be grateful for any advice on how to fit the pump to the valve.

Thanks.


Edit: All the above info about car caps and bike caps was to prove that I have a schrader valve rather than a presta valve.

But I've just seen photos of these two valves here, and there's absolutely no resemblance (as many people probably know):

http://sheldonbrown.com/gloss_u-v.html#valve

So, based on these photos, my valves are definitely schrader.

From linked ebay listing From linked ebay listing

  • I think this pump may be the sort that screws in place on Presta valves but just pushes down over Schrader to inflate. – Nathan Knutson Apr 19 '18 at 16:16
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    But in my OP I mention that the pump screws on to my car valves, and I managed to screw it on to ONE valve out of four on the bikes. It's definitely a screw fitting. It screws on, and then unscrews off. Can I put a drop of 3-in-1 oil on the valve threads, or WD-40? Or is that a no-no? – OldGrantonian Apr 19 '18 at 19:27
  • Light 3-in-1 oil would be fine - it could be a sharp thread, and after a little usage might work better. I've got an identical hose on my topeak mini pumps, and it is a bit of a fag to get on. Try bringing the hose down onto the valve stem as much as possible, even if you have to thread it between the spokes a bit. – Criggie Apr 20 '18 at 2:14
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    @Criggie. I reserve the right to silly thoughts on this thread, thanks :-) The second link in my OP shows a Woods valve, which is what we used 50 years ago (although it never had a name, AFAIK). The distinguishing features are the knurled sleeve to contain the tubing, and the threaded anchor ring to prevent the valve from disappearing inside the rim during a flat - which occurred twice a week. – OldGrantonian Apr 20 '18 at 7:58
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    Possible duplicate of Valve Extender for Kids Bike – RoboKaren Oct 24 '18 at 7:08
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Angled valve-pump adapters help in those cases. Google them, or ask at local bicycle shops.

As an example, something like Topeak's "Pressure-Rite" Schrader adaptor.

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    Best not to just post links to "this", since links often die. In this case, the product name was included in the URL anyway, but I edited to include it in the post. – David Richerby Oct 23 '18 at 17:52

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