|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
understanding the RockShox suspension pump and valve
When I first got the pump, I filled the chamber
to exactly 120psi. The release button and the gauge on the RockShox suspension pump makes this easy to do to a high degree of precision. The other day I thought I'd try it again and I noticed it took four strokes to get it up to 120psi again! Is this some property of the gauge? How much psi enters the chamber for every stroke? Or did the seemingly (?) missing amount leave the chamber when connecting the pump to the valve? Or is there a small-but-steady leak from the chamber from normal usage? -- underground experts united http://user.it.uu.se/~embe8573 |
Ads |
#2
|
|||
|
|||
understanding the RockShox suspension pump and valve
On 2018-11-06, Emanuel Berg wrote:
When I first got the pump, I filled the chamber to exactly 120psi. The release button and the gauge on the RockShox suspension pump makes this easy to do to a high degree of precision. The other day I thought I'd try it again and I noticed it took four strokes to get it up to 120psi again! Is this some property of the gauge? I have the same pump. It's a common one, resold under many brand names, probably because it's inexpensive and works well. Possibilities: - loss of a small amount of air when disconnecting pump - shock--pump pressure equalization when connecting pump - slow leak from shock - gauge hysteresis or inaccuracy At a guess, I'd rate them in that order of likelihood. -- Gregory S. Sutter Mostly Harmless http://zer0.org/~gsutter/ |
#3
|
|||
|
|||
understanding the RockShox suspension pump and valve
Thanks!
|
#4
|
|||
|
|||
understanding the RockShox suspension pump and valve
Gregory Sutter wrote:
I have the same pump. It's a common one, resold under many brand names, probably because it's inexpensive and works well. Possibilities: - loss of a small amount of air when disconnecting pump - shock--pump pressure equalization when connecting pump - slow leak from shock - gauge hysteresis or inaccuracy At a guess, I'd rate them in that order of likelihood. I think you are right because "slow leak from shock", wouldn't that mean the chamber would be *empty* pretty soon? So if we believe in your reasons 1 and 2, what is the implication of that? Say you want 120psi, maybe you should put in 120psi and then some - 125psi? -- underground experts united http://user.it.uu.se/~embe8573 |
#5
|
|||
|
|||
understanding the RockShox suspension pump and valve
On Monday, November 26, 2018 at 4:41:42 PM UTC-5, Emanuel Berg wrote:
Gregory Sutter wrote: I have the same pump. It's a common one, resold under many brand names, probably because it's inexpensive and works well. Possibilities: - loss of a small amount of air when disconnecting pump - shock--pump pressure equalization when connecting pump - slow leak from shock - gauge hysteresis or inaccuracy At a guess, I'd rate them in that order of likelihood. I think you are right because "slow leak from shock", wouldn't that mean the chamber would be *empty* pretty soon? So if we believe in your reasons 1 and 2, what is the implication of that? Say you want 120psi, maybe you should put in 120psi and then some - 125psi? -- underground experts united http://user.it.uu.se/~embe8573 Sometimes a slow leak in a bicycle tire will only drop pressure to a certain point wherein the pressure is now low enough that the slow leak stops until the pressure is topped up by the user again. Perhaps the same thing is happening with your shocks? Cheers |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Dual valve floor pump only pushes air out the Schrader valve hole | Brad Ford | Techniques | 19 | November 25th 18 05:15 AM |
Wanted 1" suspension forks manitou,rockshox etc or just the steerer section | GPNT | Techniques | 1 | February 4th 13 10:03 PM |
FS-Rockshox Suspension Seatpost 26.8, $25 | Andy | Marketplace | 0 | November 8th 07 03:54 PM |
pump valve stuck | beerismygas | Techniques | 4 | August 6th 07 01:18 AM |
Puncture/schrader valve/pump question | Premal P. Vora | Techniques | 5 | October 17th 06 06:46 PM |