Best shock pump?

[kev8pt]

Can anyone out there recommend a good shock pump? I lose 50lbs of pressure removing my Wrench Force shock pump from my rear shock. This is the second one I've tried - the first was a Topeak with a faulty release valve that let all the air out of my shock in about a half a second after attaching it to the shock.

Thanks,

Kevin

[fisherking]

I picked up a Specialized one from the bike shop and was very surprised that it was only $25 and it works great!! Needed it quick so I was willing to pay a little more and ended up very satisifed.

[Slappy]

How do you know you're losing 50lbs of pressure? Is it that when you put the pump back on, it shows that much less? That pressure is most likely being lost when you re-attach the pump rather than when detaching it.
The escaping air you hear when you detach the pump is air from the pump hose rather than air escaping from the shock itself. I'm pretty sure all models will do the same thing. When you re-attach the pump to the shock, 50psi worth of air is leaving the shock to fill the hose and pump body, that's why you get the lower pressure reading.

[kev8pt]

I hadn't considered that. The instructions for the pump do indicate that the sound of air when the pump is removed is coming from the pump and not the shock - I put the pump back on to double check the pressure, and found it 50lbs low - I immediately blamed the removal and not the attachment. I hope you're right - then I don't need to replace the pump, and I'll be able to get the pressure I need. I'll double check when I get home from work today.

Thanks for replying, Slappy!

[hammerhead]

The easiest way to tell is to test the sag before and after you remove the pump. My guess is - no change.

[Slappy]

Right on - good suggestion Harold.

[xcslowpoke]

Have to agree with Slappy and Hammerhead here, remember a shock pump is high pressure low volume. So check the sag and your probably okay.

As to Slappy's thought, its very similar to pumping up your tire. Ever notice that the pressure gauge reads zero until a few strokes of the pump. This is because it needs air to fill up the hose prior to actually getting air into the tire. Also when you remove it, the air comes out of the hose. It has to do with the pressure to square area, thats the loud sound.

If you truely are loosing 50 psi, I would check the valve stem next. Might not be seating quick enough.

I have used the standard OEM pumps from RS or Fox for years w/o issue.

[Slappy]

If you truely are loosing 50 psi, I would check the valve stem next. Might not be seating quick enough.

That reminds me - I did have a valve stem fail on a fox shock once. One day I rode it 30-something miles with the lock-out engaged and after that it just wouldn't hold air at all. Figured I'd try a few things before sending it out so I stole a stem out of a schraeder tube and the thing's been fine ever since.
I love cheap fixes. :D

[heckler]

I have a couple of shock pumps that behave nicely. The one I carry most often is a Buzzy's Pollentor Shock pump (bought from Bikeway Source in Bedford).

I am unaware of ever losing air putting it on or taking it off. The hose is so short that the volume that goes from the shock into the pump is real small so it seems to read the same time after time. I can put it on, take it off, put it on again and get the same reading- within a couple psi. Less loss than with a gauge, for sure.

[kev8pt]

Thanks for all the good info. I think mine is a case of operator error. I'm completely new to FS, so this is all relatively new to me. The information I now have should enable me to set my suspension up pretty confidently and accurately.