Are all Presta cores the same quality?
09-23-23 | 11:12 AM
#26
Senior Member
Joined: Sep 2005
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From: Michigan
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
What hose are using with the Hirame head? Thanks.
09-23-23 | 11:17 AM
#27
aged to perfection
Joined: Jun 2009
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From: PacNW
Bikes: Dinucci Allez 2.0, Richard Sachs, Alex Singer, Serotta, Masi GC, Raleigh Pro Mk.1, Hetchins, etc
All the Hirame stuff is available from Alex Cycles. When I buy items that I am determined to use, I add any spare parts that wear out to the order, so I would just need to go to my bin if I needed something.
What hose are using with the Hirame head? Thanks.
What hose are using with the Hirame head? Thanks.
As for the hose - I think that is braided pneumatic hose. You can also use Bosch or Conti fuel injection hose which is good for 300 psi.
For bike tire pumps you want 6.5 mm / 1/4 in ID.
/markp
09-23-23 | 01:34 PM
#28
Old fart
Joined: Nov 2004
Posts: 26,411
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From: Appleton WI
Bikes: Several, mostly not name brands.
A while ago one of my Presta valves failed. The thin inner rod broke. I suspect I have been a little careless in the past with how I put the pump head on (it's the first bike I've had with Presta tubes). I'll try to do better. That was a non removable core, so I had to throw a perfectly good tube away.
Both tyres now have removable cores, so I thought I'd get some spares. I'll probably replace the core on the non new tyre anyway, in case I've damaged that.
But there seems to be a huge difference in price. 4 x Schwalbe cores are something like £14 (UK). Whereas a pack of 12 unknown-make are £7. Is there much difference in quality? I assume they're all the same size. And I don't really need 12.
But there seems to be a huge difference in price. 4 x Schwalbe cores are something like £14 (UK). Whereas a pack of 12 unknown-make are £7. Is there much difference in quality? I assume they're all the same size. And I don't really need 12.
09-25-23 | 02:58 AM
#29
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Joined: Sep 2005
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From: Michigan
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
I am still away from my base for a few weeks, but I vaguely remember that there was something different about the hoses Lezyne utilized. Certainly, the OD needed to fit too, but maybe the nominal ID was different as well.
09-26-23 | 06:01 AM
#30
Senior Member
Joined: Jul 2014
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I just had another failure last night. Went to top off my tires and couldn't on one of them. Changing the valve fixed the problem.
I've certainly seen more bad presta valves in the last few years than I've seen my entire life. We know that not all low-cost things produced in China are junk, but some of them certainly are. This looks like an example.
I mentioned above how much better the replacements from Amazon are than what I've pulled out of tubes lately. I looked at them side by side under a low-power stereo microscope (because I could) but even with just a strong magnifying glass the difference in quality is apparent. Both the materials and the fit and finish are significantly better on the replacements.
It's a shame that now I have to just assume any new tube will come with a junk valve, even Schwalbe or Continental tubes, and now just replace them automatically. And now I always carry a spare, which I didn't use to.
I've certainly seen more bad presta valves in the last few years than I've seen my entire life. We know that not all low-cost things produced in China are junk, but some of them certainly are. This looks like an example.
I mentioned above how much better the replacements from Amazon are than what I've pulled out of tubes lately. I looked at them side by side under a low-power stereo microscope (because I could) but even with just a strong magnifying glass the difference in quality is apparent. Both the materials and the fit and finish are significantly better on the replacements.
It's a shame that now I have to just assume any new tube will come with a junk valve, even Schwalbe or Continental tubes, and now just replace them automatically. And now I always carry a spare, which I didn't use to.
Last edited by Jeff Neese; 09-26-23 at 06:05 AM.
09-26-23 | 10:18 AM
#31
Senior Member
Joined: Aug 2009
Posts: 4,311
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I recently encountered a 'bad' valve core. This valve core worked fine in its original tube. It just doesn't work once I put a valve extender on there. The issue was that the tapered rubber ring was too big and loose. So when I tried to pump with the air compressor, it swelled (swole?) up and blocked the air. I am guessing the extender has a slightly smaller ID than the original tube valve.
I replaced it out with a Continental valve core and all was fine. The Continental valve core has a noticeably tighter fitting rubber sealing ring.
I replaced it out with a Continental valve core and all was fine. The Continental valve core has a noticeably tighter fitting rubber sealing ring.
