How to pump up front air shock?

Okay, another newbie question. My front shock is bobbing like a pogo stick. It's all well and good on rooty trails, but when I go to ride a gravel road, I can't climb well at all because of all the pogoing. The problem is that I have no idea how to add air, which I'd like to do for a fireroad ride planned for this week.

Here's the fork I have: Rockshox SID Dual Air 2000

I have a high-pressure air shock pump (brand name unknown, given to me by a friend) that works fine on my rear shock, which has a Schrader valve.

From the manual I found on the Rockshox site, I see that my fork has a positive air and negative air valve ("dual air"). I understand that the positive air valve is at the top of the left fork leg. I am not quite sure if the negative air valve is at the top of the right fork leg (which appears just like the left fork leg) or at the bottom of the left fork leg, where there is yet another valve. So that's my first question.

My next question is how to pump them up. The directions say to pump them with a high-pressure pump with schrader valve. I guess something is missing, because the valves on my fork do not stick out, they are recessed with threads inside them, so I guess my pump itself needs a schrader valve to screw into them? I've looked at a lot of pictures of shock pumps online, and they all look just like mine - they end in a female connector that screws into a schrader valve. Or is my fork missing an adapter of some type? I bought the bike used, so who knows if it came with everything. The LBS pumped the shock for me initially when they were doing other repair work on the bike, but I have no idea how and don't want to take it there for something that should be an easy DIY task!

Here are a couple of photos - one showing the valve hole at the top of the left fork leg, and one showing the valve hole at the bottom of the fork leg:

http://home.earthlink.net/~emilys7/c.../top_valve.jpg

http://home.earthlink.net/~emilys7/c...ttom_valve.jpg

I've done a lot of web searching but have not been able to figure this out and feel so stupid!

Thanks for any help you can give this clueless newbie to mountain bikes. :confused:

Emily

Hi Emily,

I just unscrewed the top cap off my fork - it's different to yours, it's a Rock Shox Tora (this years) and it has a schrader valve sticking out like a schrader tube would have. My pump connects to this. The pump I have is just a giant brand.

Since I don't have negative air (only positive air in one leg) I would say that your bottom valve is for negative air & the top for positive. I know the Rock Shox Reba Fork comes with positive & negative air so you could google on that for an idea of settings - if you can't find anything on yours.

Sorry I can't help with your other question but to me it does look like something is missing - or it's made for a different pump. If you get nowhere ask your LBS or Rock Shox themselves. It's a fair enough question.

I found this on the sram / rockshox site, you may find it useful down the track even if it doesn't answer your current problem (I haven't read it in detail myself).

http://www.sram.com/_media/techdocs/...rviceGuide.pdf

Quote:

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Originally Posted by emily_in_nc

Okay, another newbie question. My front shock is bobbing like a pogo stick. It's all well and good on rooty trails, but when I go to ride a gravel road, I can't climb well at all because of all the pogoing. The problem is that I have no idea how to add air, which I'd like to do for a fireroad ride planned for this week.

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In addition to adding air, did you adjust your compression/rebound settings also?

Quote:

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Originally Posted by emily_in_nc

From the manual I found on the Rockshox site, I see that my fork has a positive air and negative air valve ("dual air"). I understand that the positive air valve is at the top of the left fork leg. I am not quite sure if the negative air valve is at the top of the right fork leg (which appears just like the left fork leg) or at the bottom of the left fork leg, where there is yet another valve. So that's my first question.

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One valve is on top and the other should be on the bottom. (I have a Reba R.S. front fork). I think the manual recommends that you set them to the same pressure, then go from there.

Quote:

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Originally Posted by emily_in_nc

My next question is how to pump them up. The directions say to pump them with a high-pressure pump with schrader valve. I guess something is missing, because the valves on my fork do not stick out, they are recessed with threads inside them, so I guess my pump itself needs a schrader valve to screw into them? I've looked at a lot of pictures of shock pumps online, and they all look just like mine - they end in a female connector that screws into a schrader valve. Or is my fork missing an adapter of some type? I bought the bike used, so who knows if it came with everything. The LBS pumped the shock for me initially when they were doing other repair work on the bike, but I have no idea how and don't want to take it there for something that should be an easy DIY task!

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On my R.S. front shock, I have to remove covers to get to the valves. My shock pump just screws on to the valve. The fitting on the end of the shock pump looks like a metallic cyclinder and it is internally threaded. I'm not quite sure from your pictures what is going on. In the first picture, did you remove a cap? Or is it just exposed? It certainly doesn't look like a shock pump with a schrader fitting is going to work. If no one on this message board can help you with this, you should call Rock Shox and ask. I'm sure they could answer this easily.

http://www.sram.com/en/rockshox/index.php

Thanks for the helpful information! I kept digging around and finally found this thread on mtbr.com. This guy has a 98 SID fork, so slightly different than mine but with some similarities. Turns out we both need a needle adapter for our shock pump. These are the type of adapters that are used to pump up footballs! Interestingly enough, my DH, being the sports fanatic that he is, says he has one. We'll see if it will work with my shock and pump. Apparently in later models, Rockshox went to regular schrader valves on their forks. There's also an option of purchasing one of these to replace the top cover on my fork, but if the needle valve works, I won't bother. I'm sure a new fork is in my future as I'd love to have lockout capability for certain types of riding, but I don't want to spend the money now, and I do love the blue color of my fork!

Emily

Glad you've got that sorted!

My fork has a remote lockout - but I threaded the remote that mounts to the handlebar. Anyway I've taken the lockout off the fork now and really the only place I would miss it is when riding on the road (butument, tar, whatever you like to call it).
In some ways lockouts are a bit overrated I reckon. I certainly wouldn't specifically go for a pop lock remote one myself next time around - leg mounted controls would be fine.

Quote:

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Originally Posted by Pebble

In some ways lockouts are a bit overrated I reckon.

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Mine is invaluable.....for racing and hill climbing in general. Though I have a simpler version of the poplock.

The top valve cover might be a good investment. Bubba and I will frequently carry an airshock with us on the trail if we're trying to fine tune a fork or not sure about the conditions. If your fork is running a little soft and you suddenly find you're taking bigger hits and bottoming out, it sure is nice to pump up the fork a bit. Having to carry the needle and sort it all out on the trail sounds a bit complicated when there is a simple solution that makes your fork compatible with standard pumps.

Think carefully about putting money into a lock out. IMHO, it's just money and weight. They generally blow out anyway because you forget to unlock them before hitting the trail.

I have lockouts front and rear on my Racer X and never use them. I did a couple times on pavement when the bike was new but then realized it's just a good excuse to work on smoothing out my pedal stroke. Racer X's excell at climbing anyway so you shouldn't need one climbing on the trail. I mean, the first thing I noticed about my Racer X was she was going up the hill with me or without me so hang-on!

Quote:

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Originally Posted by SadieKate

The top valve cover might be a good investment. Bubba and I will frequently carry an airshock with us on the trail if we're trying to fine tune a fork or not sure about the conditions. If your fork is running a little soft and you suddenly find you're taking bigger hits and bottoming out, it sure is nice to pump up the fork a bit. Having to carry the needle and sort it all out on the trail sounds a bit complicated when there is a simple solution that makes your fork compatible with standard pumps.

Think carefully about putting money into a lock out. IMHO, it's just money and weight. They generally blow out anyway because you forget to unlock them before hitting the trail.

I have lockouts front and rear on my Racer X and never use them. I did a couple times on pavement when the bike was new but then realized it's just a good excuse to work on smoothing out my pedal stroke. Racer X's excell at climbing anyway so you shouldn't need one climbing on the trail. I mean, the first thing I noticed about my Racer X was she was going up the hill with me or without me so hang-on!

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All good points - thanks! I got a lot more detailed info from the mtbr.com forums since I last posted. Turns out I need more than a regular needle adapter; I need a special SID adapter, made only for '99-'00 SID forks. I found one online at airbomb.com for only $4.38! But in the meantime, DH was able to rig one up from a needle adapter and a plastic cap, and pump up my fork with his air compressor. Wow - it's so much firmer. He said it was pretty much completely out of air, so no wonder I was pogoing like crazy!

The reason I am considering a fork with lockout eventually is that I frequently ride fire roads with LONG climbs. However, now that I have my fork pumped up properly (since I'm doing a fire road ride tomorrow), hopefully it will be much better than my last pogoing experience. I also have my rear shock pumped pretty firm. My mtb buddies recommend front forks with lockout for this type of situation, but you do make a good point -- better not forget it's on before hitting a singletrack trail!

I'll have to think about buying the valve covers; I'd need to spend about $50 to get one for each side of the fork, and then there's still the negative air chamber in the bottom of the left leg of the fork that I wouldn't be able to deal with on the trail; but I could at least pump up the positive air on the fly with my shock pump with these (though I currently don't carry it with me when I ride -- nowhere to put it! Just not sure I want to spend even $50 if I plan to buy a new fork next spring. I won't be doing a lot of riding over the winter -- that's hiking season for DH and me. :)

Emily