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Old 01-03-05, 09:10 AM   #1
phantomcow2
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a stupid question about shock pumps

I am getting an air fork for the first time. I see the place where air enters ia a schrader valve, I have a pump that has the head for a schrader. So is there any reason i could not use a regular pump with a guage for this thing? try to bare with me here
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Old 01-03-05, 09:16 AM   #2
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I assume you're talking about a bicycle pump? Mine would not produce enough pressure to pump up the rear shock(Fox Alps 5r) on my DS. I borrowed a shock pump from a co-worker. Not sure how much they cost, but I don't think there's much else that'll work for this application. Air forks might be lower pressure?
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Old 01-03-05, 10:26 AM   #3
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A regular bike pump will push to much volume at to low a pressure for most suspension applications. You might be able to get away with it if you only need to get up around 100psi, but anything over that will be a PIA. Also you won't be able to fine tune the suspension since floor pumps do not have bleed valves.

I caved and bought a Rock Shox shock pump about a year ago, about 30 bucks from Colorado Cyclist. Gauge reads up to 300psi and has a nice little button bleed valve built in.
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Old 01-03-05, 10:31 AM   #4
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Rock shox forks and most rear shocks must have pressure in excess of 120psi, beyond the rating of a tire pump. Marzocchi forks use no more than 45psi which puts them in the range of normal hand pumps. The problem though is the chamber is so small within the fork that when you remove the valve it releases a large percentage of your pressure. I used to have to fill my Marzocci that way(what a pain).
Genuine shock pumps have a small barrel to get precise metered fill, as well as a guage. But the thing that sets it apart is called a Zero-loss fitting. It threads onto the shrader and will not push the pin until it is sealed onto the body. More importantly it releases the pin before it releases the seal on the valve body, so the loss is reduced to a very minor ammout.
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Old 01-03-05, 10:33 AM   #5
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Quote:
Originally Posted by phantomcow2
I am getting an air fork for the first time. I see the place where air enters ia a schrader valve, I have a pump that has the head for a schrader. So is there any reason i could not use a regular pump with a guage for this thing? try to bare with me here
Technically it will work, but it will be impractical:

1. The volume needed is relatively small - it'd be hard to regulate the amount of air introduced to the shock.

2. The fork valve may not be configured to accept a "squeezed-on" pump head, which is typical of most bicycle pumps. The valve usually protrudes 1/2 inch and it may not be enough for the pump to grab onto. Fork pumps have "screw-on" heads.

3. It could be hard to set the correct pressure with a larger pump. Most fork/shock pumps have a micro-air release button, which allows you to remove very tiny amounts of air to adjust the internal pressure. For example, you can pump it up to 95 lbs, and hit this button 10 times to bring the internal pressure down to 90 psi.

4. Fork and shock pumps are more like fine precision instruments, while tire pumps are meant to deliver a lot of air with the fewest strokes. A shock pump is almost opposite - small volumes of air with a lot of strokes but with great accuracy.
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Old 01-03-05, 03:46 PM   #6
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alright thanks for clearing that up. I've come to the conclusion that the 25 dollars for the shockpump is worth it to avoid the annoyingness
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Old 01-03-05, 04:59 PM   #7
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alright thanks for clearing that up. I've come to the conclusion that the 25 dollars for the shockpump is worth it to avoid the annoyingness
Sometimes you gotta bite the bullet - I don't think there's getting around this one. Unless you have a friend that has one. I don't use mine that much. I may check pressure on my fork/shocks once a month. But, you can't live without one. Once you feel the ride from an air shock, you'll forget about the $25.
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Old 01-03-05, 05:11 PM   #8
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Amen!
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Old 01-03-05, 05:22 PM   #9
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Or buy more bikes to fill the need. I now own 3 forks that can use the shock pump. well worth the money and time
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Old 01-03-05, 07:20 PM   #10
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Any recomendations out there? If its under 30 dollars that ideal
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Old 01-03-05, 11:25 PM   #11
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THey are almost always going to run 20 bucks +- a couple. I wouldn't pay any more than 25.
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