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Help something weird going on with my fork
Need some help. When pumping air into my fork it seems ok until it reaches around 60psi. Then as I try to pump more air it shoots up to 100psi. I can feel quite a lot of resistance if I try to pump any more . The needle on the gauge gradually goes down. I've tried another pump but same thing. Is the air not going into the fork but just filling the hose on the pump? Any help appreciated
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check the end that screws onto the valve.. check that it is all tight etc and hasn't undone itself slightly from the hose. Some of the heads screw apart for cleaning etc. Mine did this about a year ago, and when I threaded it onto the fork valve, it didn't press in the valve core and hence only pressurized the pump hose and not the shock. after tightening the head assembly back up the problem was sorted.
Pete
Stuck valve core? You can get a little tool from the auto accessories place to remove them and a regular Schrader valve core will be a drop in replacement.
Might try the valve core remover but where do I get a new valve core from? Auto shops?
where do you live.. any tyre shop would be able to help.
or drop by my work in Forrestfield and I'll give you one, if I have one small enough.
pm me if near.
Pete
If the pump has a bleeder on it that will let you know if the pump has depressed the valve properly. If you can bleed air out it should be fine if not it will take quite a lot more pressure at the pump to open the valve as there is more surface area on the bottom of the valve than the top.
My stupid Lezyne tyre pump requires you to wind a Presta valve way up or it relies on air pressure to open the valve, then it tries to screw the core out when you take it off(plus it kills your hand, fills with the barrel with dirt and the bracket is so crap my frame is losing paint), I swear Lezyne is a sister brand of Crank Brothers, as long as it looks flash it's good to sell.
Ozgti, I'd go with the valve core having a problem.
I've never taken one out of a shock but I imagine they're just a standard car schrader valve, albeit a short one as Fairy1 said.
Might sound silly but make sure you've let all the air out of the shock before you start unscrewing the core. A core firing out at full pressure could be quite a embarrassment...
So there are different size valve cores? Fairy1 what do you mean by bleeder on the pump? Don't think it's the pump seeing I've tried 2 and it does the same thing. So if it can let air out, is it still the valves core?
Yeah, for some reason, valve cores come in various lengths. Not sure why. The extra length is on the spring end (inner end). The shortest one is about 15mm.
You can even pick them up off the ground around service stations if they fit/repair tyres. And some long valve-stem tubes as you find on some 4wd and trucks, have caps that have a core tool built in. There's usually a small rubber boot covering it.
There's certainly no harm in removing the core to check its length anyway (Let the air out!!!) Who knows, you might even find the problem, blow away the little bit of crap that causing it and be back in business!
Considering you tried 2 pumps, I'd expect it to be the valve, although Fairy1's suggestion can't be dismissed until you've tried it. Most shock pumps have a bleeder button that lets air out of the whole system when you press it, just in case you went over the required pressure.
Good luck!
The shocky pumps I've used have a small screw on the end that allows you to close off the schrader valve before removing the pump fitting. Check that the screw is in or out the right amount.