A very dull thread ...
 

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[Closed] A very dull thread about valves.

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What is the advantage of a Presta over a Schrader? Is it just the smaller diameter of the hole in the rim?

My fleet are currently running a mixture of both types apart from the CX which has no front wheel in it at the moment because I snapped the little thingy out of the Presta whilst removing the pump.

A £5 lesson in cack-handedness and a trip to the LBS at lunch time.


 
Posted : 29/06/2010 7:56 am
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i dont really know, i've asked this question myself. Sometimes people come in at work (halfords!) and ask me for "high pressure valves" when they buy inner tubes. In reality they want it for a mountain bike so the pressures not going ot matter with either valve.

I have also drilled road rims and run schraeder valves at 110psi at the moment. No loss of air. Perhaps they will eventually blow out the inside of the valve or something??? 😯


 
Posted : 29/06/2010 8:07 am
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Scraeder are for cars and motorbikes, presta for real bikes.

Them's the rules!


 
Posted : 29/06/2010 8:07 am
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Scraeder are for cars and motorbikes, presta for real bikes.

Them's the rules!

He's right you know.


 
Posted : 29/06/2010 8:08 am
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advantages of schraeder -

[list]You can buy them for £1 in poundland
they still have removable cores so its easier to deflate them or put slime in[/list]


 
Posted : 29/06/2010 8:11 am
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Presta (bike type) have a valve built into them, so work with mini hand pumps and track pumps where the valve is designed to flow as much air as possible

Shrader 'valves' are held open by the pump and rely on the valve inside the pump to stop air going back, which is why they release air when you push the pump on but dont close the clamp.

Yes, you could put the end of a shock pump on a shrader valve pump, but this would be fiddly when a presta valve is smaller so less force pushing it off the pump so a lot of hand pumps can rely on the weight of the wheel to hold the valve onto the pump rather than needing any extra clamping mechanism.


 
Posted : 29/06/2010 8:14 am
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Scraeder are for cars and motorbikes.
and caravans and tractors.

I think that Presta are for ladies or men with suspiciously small hands.


 
Posted : 29/06/2010 8:15 am
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Smaller hole in the rim. Lighter. Positive seal.


 
Posted : 29/06/2010 8:16 am
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Presta = broken
Schraeder = stuck


 
Posted : 29/06/2010 9:17 am
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they still have removable cores so its easier to deflate them or put slime in

decent presta valved tubes (Schwalbe) still have removable cores as well.


 
Posted : 29/06/2010 12:12 pm
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rootes - find me a presta valved inner tube for a £1 with removable cores.


 
Posted : 29/06/2010 12:16 pm
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rootes - find me a presta valved inner tube for a £1 with removable cores.

i can't schwalbe are £4.99 - but i did say decent tubes not rubbish ones

didn't know there was a £1 limit... 🙄

Si


 
Posted : 30/06/2010 4:01 pm
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Presta = broken
Schraeder = stuck

Looks like we need a new standard!

Oversized tapered latex-coated valves are 2011's 'must have' item! 😛


 
Posted : 30/06/2010 4:29 pm
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Shrader 'valves' are held open by the pump and rely on the valve inside the pump to stop air going back

Not with all pumps. Certainly not with mine. The valve opens due to pressure differential.

Schraeder valves can fill with mud if you haven't got the valve cap.....


 
Posted : 30/06/2010 4:42 pm
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I was once told by a man who professed to know things .. that calling presta the 'high pressure valve' is something of a misnomer - as (apparently) schrader valves are rated up to a much higher (400?) psi than presta - in other (industrial) applications

No doubt someone will soon weigh in with "Well.. I'm an engineer and.."


 
Posted : 30/06/2010 4:52 pm
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That sounds reasonable.. after all, what valves do shocks and forks have?


 
Posted : 30/06/2010 4:54 pm
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I always thought that Presta valves were used because it's rather dodgy to drill such a large hole in thin road rims.


 
Posted : 30/06/2010 5:19 pm

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