An easy to use track pump head?

[rjb]

I had to inflate my car tyres yesterday as they all had lost approx 5psi and I noticed it when driving as the steering became vague, not tight as normal. Trying to use my track pump with the twin head connector meant bending the valve to a horrible angle to get it on. I could have made it easier by removing the wheel trims, but this could lead to other problems so I left them in situ. BTW The wheel trims don't need removing to change the wheel. An adaptor sounds a good idea. Are extension adaptors made for Schrader valves?

[Brucey]

angled car valve stems commonly deform at speed so that the stem lays against the rim. If you can't safely bend the valve stem to get a pump on, probably you need new valve stems.

cheers

[DaveP]

Bother! Fully intended to specify Schrader valves and road pressures, but it was getting late...
I've never understood how they became so popular for bikes - why have a bigger hole in that narrow rim, than you have to? I only have one bike now that uses Presta, I have an adaptor for it that sort of works, but usually I use its onboard Zefal HPX - which I can handle quite successfully. Hhmmm. Food for thought...
At the moment, I let down the Brompton tyres, by way of checking the pressure about twice a week. Definitely not a Team scale user!
I currently have a twenty odd year old Silca. Pump works fine, but apparently when it needs a new washer I will have to make one as they changed the bore. The original hose has been shortened over the years and is now too short for convenience. Currently has a Zefal lever action head which is the focus of my current dificulties.
If I bought the Lezyne flip head I would obviously need a coupling and hose as well, at a cost over half way to that of an entry level pump, and with no real idea about compatibility. Perhaps, after all, its just time to buy new - If only I could afford an accountant - I'd just get me an air line!

[Mick F]

Lezyne Airbleed.

The airbleed is for bleeding the pressure from the hose.

Screws on easily.
Pump to required pressure ......... Mercian rear sits at 120psi and Moulton rear at 100psi.
Press the bleed button to release the pressure in the hose only.
Unscrew easily.
Hardly any friction in screwing or unscrewing.

--------------------------------

Told this story before.
I had a track pump some time back and heard all sorts of good news about the Topeak Twinhead. so I bought one and fitted it.
It lighter and easier to use than the original.

Then, I realised something.
It took me a few years before I saw the light.

When you connect up and fill the tyre to nice and hard at 100psi plus, when you release, some air is lost from the tyre.
Repeat a few times connecting, and disconnecting, and slowly you'll end up with a soggy tyre.

Easy to experiment.
Pump to required pressure and remove, then connect a pressure gauge to measure.
Repeat.
You will find that the pressure is now reduced.

Try that with the Lezyne Airbleed, and you'll find no such issue.

Ok, you might say that my Topeak was defective .......... and that's what I thought, so I bought a new set of seals for it. Same issue persisted.

No doubt they are fine at "normal" pressures, but when you want 100psi+, the unit needs to be on firmly so it doesn't blow off. Consequently, the Presta valve is opened a tad so when you disconnect, a bit of air escapes.

So what?
Does it matter?
I mattered to me, so I chucked it away.

[philvantwo]

Orange button on the side of the pump by the gauge on my Joeblow sprint, press it when you're up to pressure and it releases the pressure in the hose.
Had 2 things from lezyne, both were complete rubbish so I chucked them away.

[Brucey]

Told this story before..

yes and the same advice applies; don't use connectors which open presta valves, or ones that are meant not to, which you have pushed on too far.

IME Topeak Twinhead connectors are pretty good if used correctly, but prone to all kinds of issues if used incorrectly.

cheers

[Mick F]

............. the "incorrectly" word is the point here.

They do not work at 120psi unless their seals go onto the parallel part of a Presta valve.
The unit isn't deep enough to cope without pressing the valve a tiny bit.
The Lezyne one is threaded on, so doesn't rely on friction.

I'm out of this subject.
Said my piece, and I stand by it.

[squeaker]

Been using one of these for a short while. Maybe just a different fiddle to get on, but certainly no big levers to flip, and the release action pulls the head off the valve.

[Jdsk]

Jonathan

[belgiangoth]

Are these fairly universal, or do I need to get the vernier calipers out?
And, any recommendations?

[Jdsk]

I wouldn't assume that they all fit all hoses.

Recent discussion, including my recommendation:
https://forum.cyclinguk.org/viewtopic.php?f=5&t=141962&hilit=pump+heads

Jonathan

[rotavator]

When the head started leaking on my Specialized track pump I got a Topeak Joe Blow head which came with various fittings and a piece of hoze. The instructions showed various ways of attaching it and I fitted it without problem, in fact I prefer it to the original Spec head.

[Graham]

Topics merged

[531colin]

Not so much thread drift, more a completely different question..

..........valve cores are almost invariably brass. Brass is much the best material for a chuck too, especially a screw-on one; it has a noticeably lower coefficient of dry friction and doesn't tend to gall. .........

Is this why old-fashioned brass playground slides are so much faster than modern stainless ones, which are sticky by comparison?

[Brucey]

Not so much thread drift, more a completely different question..

..........valve cores are almost invariably brass. Brass is much the best material for a chuck too, especially a screw-on one; it has a noticeably lower coefficient of dry friction and doesn't tend to gall. .........

Is this why old-fashioned brass playground slides are so much faster than modern stainless ones, which are sticky by comparison?

Honestly, I don't know. Then again it is (damp) cloth on metal friction, not metal on metal friction. A different thing altogether...?

Having said that, Brass is also low friction (relatively speaking) vs dry (hard) steel too.

cheers