Shock pump klutz

[Flog]

Why does it take me at least 6 or 7 goes at pumping up my shock and getting the pump off without letting 90% of the blessed air out!
I'm pretty heavy so have it pumped up pretty high and every time I do, I let more out than goes in. Is there an experienced pumper out there with a solid gold tip - or do I just need to be more human and less ape like!!

 

[KennyB]

When you take the pump off, unscrew the pump body from the connector on the valve, then unscrew the connector. You only lose what is in the hose.

 

[STATO]

Why does it take me at least 6 or 7 goes at pumping up my shock and getting the pump off without letting 90% of the blessed air out!
I'm pretty heavy so have it pumped up pretty high and every time I do, I let more out than goes in. Is there an experienced pumper out there with a solid gold tip - or do I just need to be more human and less ape like!!

Are you using a proper shock pump?

A proper shock pump will have a seal before the threads, meaning the head of the pump is still sealed and holds air as you unscrew. As you unscrew the pin in the head no longer connects with the shock valve core meaning shock air chamber is now sealed but obviously you still have pressure in the pump, as you finally unscrew the pump the pressure in the pump is released, but not the air in the shock. In summary, you are not letting any air out.

When you connect the pump to the shock and screw it down the seal engages before the valve is depressed, meaning air in the shock is not lost. However, the pump is at 0psi, so when the valve is finally depressed the air in the shock has to pressurise the volume of the pump, in doing so the total pressure of teh pump and shock drops (its just had to fill a larger volume of the pump). So when you connect a pump and get a pressure reading it will be lower than when you disconnected the pump previously. Summary, you are not letting any air out.

SO, to conclude.

Pump shock to 200psi.
Disconnect pump.
Shock is at 200psi.

Shock is at 200psi
Connect pump.
Shock and pump are now at 180psi.




You may lose air in the shock if;
You are not using a proper shock pump.
You air valve is faulty.

 

[Flog]

Yep, using. LifeLine Shock Pump | Chain Reaction Cycles
but each time I unscrew the air comes out. I will have to investigate tomorrow with your explanation. Thanks

 

[STATO]

Yep, using. LifeLine Shock Pump | Chain Reaction Cycles
but each time I unscrew the air comes out. I will have to investigate tomorrow with your explanation. Thanks

Ahh, they are a bit weird, has quite a few poor reviews explaining same issues as you. TBH im amazed they still make them like this, not seen one with this style pump head since 2001 i think . See if you can get a Fox or Rockshox pump.

 

[IanVersion2]

Looks like the red knurled bit on the back disengages the valve so I'm guessing process would be...

Unscrew red bit
Screw pump onto shock
Screw in red bit
Pump
Unscrew red bit
Unscrew pump from shock

I assume that's what you're doing and the pump is just crap but doesn't hurt to check!

 

[STATO]

Looks like the red knurled bit on the back disengages the valve so I'm guessing process would be...

Unscrew red bit
Screw pump onto shock
Screw in red bit
Pump
Unscrew red bit
Unscrew pump from shock

I assume that's what you're doing and the pump is just crap but doesn't hurt to check!

Yeah that looks right, reviews suggest a few people still have leak problems when unscrewing the red bit, crappy o-rings dont seem to be able to hold the pressure.

 

[Flog]

@IanVersion2
What..... nope, just unscrewing the whole thing. Brilliant, I can say user error, retraining required!!
I’ll try tomorrow Thank you all.

 

[Flog]

@IanVersion2
@STATO
Oooooh, I see said the blind man to his deaf son..... unscrew the red knurled and yes, it disengages the valve and screw off the pump whilst having a cuppa!! THANK YOU