Can't pump up tyre enough...

ajoten

Not a "road beginner" but feeling like one with this problem. I'm getting well riled now.

Having happily pumped up tyres to 120psi for years, changed tubes, pumped them up, changed tyres, pumped them up etc etc, I now have a situation where I can't get one beyond 100psi without the pump head popping off.

My track pump is a few years old and was cheap, but it successfully pumped up one new tyre (with old tube) but not the other new one (with new tube, a smooth valve if that makes any difference).

It must be something basic, but I'm at a loss. Any ideas?

oldwelshman

get a new valve head, anyway 90 to 100 is plenty

ugo.santalucia

Try pushing the head in less rather than more, before locking it... it seems wrong, but it works... failing that, new head valve

cougie

+1 on the 100 is plenty. 120+ PSI is sooo last decade.

ajoten

a. I'm doing whatever I can to avoid pinch flats, especially with the outrageously pot-holed tarmac around here.

b. It may well be plenty, but I'll be the judge of what pressure I have, not the pump!

c. It may well be plenty, but if the tyre says it'll go up to 145psi (which it does) I expect to be able to do it. Even if I don't want to (which I don't).

pickylongstocking

Hit a nerve have we?

cougie

The tyres may be rated up to 145 PSI - but what are the rims rated for ?

If one tyre is able to be inflated up to whatever PSI and the other isnt - then seems to be a problem with the tyres valve ? Get a new innertube ?

woodywmb

http://tinyurl.com/120psibrickhardtyres

That'll do it.

Monty Dog

There's an argument to say that anyone that hasn't learnt that hard tyres = cr@p handling and punctures is still a beginner?

slowondefy2

Commenting on 100psi vs 125psi is impossible without knowing the rider's weight, tyre width, the usual road surface type ridden on and front vs rear. So many people comment "XXXpsi is stupid and wrong" (not just in this thread) from a position of ignorance :-(

daveyroids

I would say a new valve head or if the pump was cheap maybe treat yourself to a new pump. I'm guessing that the threaded valve gave the valve head more grip therefore the worn head did not cause any problems until it had no grip on the smooth head.

By the way I would tend to pump the up hard for potholed roads. My experience tells me that at lower pressures snake bite punctures are a problem and there is a greater chance of damaging the rim when hitting pot holes, at lower pressures. Of course Sheldon Brown has covered this here http://sheldonbrown.com/tyres.html and writes about under, correct and over inflation.

oldwelshman

slowondefy2 wrote:

Commenting on 100psi vs 125psi is impossible without knowing the rider's weight, tyre width, the usual road surface type ridden on and front vs rear. So many people comment "XXXpsi is stupid and wrong" (not just in this thread) from a position of ignorance :-(

No its not. If I told you to put 60psi in your car tyre would you?
There is no benefit in having 125psi in a tyre on the roads here, I am happy for you to proove otherwise?

ajoten

No, I wouldn't put in the psi you tell me, I'd use the psi recommended in the manual. Likewise I use a psi suggested on the tyre... and according to the manufacturer's website http://www.schwalbe.com/gbl/en/technik_info/luftdruck/index.php5?flash=1&gesamt=74&ID_Land=38&ID_Sprache=2&ID_Seite=136&tn_mainPoint=Technik&tn_subPoint= I've got the right target pressure anyway.

I haven't noticed any problems with handling, but then the roads round here haven't got many hairpin bends or berms.
I have had a problem with pinch flats when I haven't been disciplined about checking my tyre pressures regularly.

The more perspicacious among you will have noticed that the original posting wasn't about the wisdom or otherwise of certain tyre pressures, it was about the inability to reach a pressure that I've happily been using for 10+ years.