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~Reformed Mechanic~
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Discussion Starter #1
I went to replace some seals on my RS Monarch RT yesterday and to my surprise I did not realize RS shocks require a special "Monarch air valve adapter" to refill the IFP... So now im stuck unable to refill it :(

Anyone else get stuck not being able to reassemble and pressurize because of this special adapter?

Here is what the little bugger looks like


TL6594.jpg
 

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~Reformed Mechanic~
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2,177 Posts
Discussion Starter #3
I would, not 1 LBS even believes me that there is a fill valve other than a Schrader on the shock, let alone has one... Sometimes I feel like I bike in the twilight zone.
 

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Tell them to call Sram and get the part number. (none of the shops near me knew what I was talking about either, so this is what I did.)

Or

Rock Shox Air valve adapter, Vivid/Monarch shock IFP | eBay

If all else fails:
PM me your address and I will mail you mine. I dont plan on buying another Monarch anytime soon. You would need to pick up an O-ring though, Mine broke and is now missing.
 

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~Reformed Mechanic~
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2,177 Posts
Discussion Starter #5
Thanks for the offer bro! Frustrating when the LBS mechanics don't have a clue what Im talking about... Their only response was No-one uses Rockshocks anymore :::face palm::: Universal Cycle had one and got it sent priority today, so hopefully will get here before the holiday weekend!
 

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~Reformed Mechanic~
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2,177 Posts
Discussion Starter #7
The adapter arrived today and I tested it out. The trouble Im having is just like when filling fork valves, when you unscrew the valve im loosing air. Im actually loosing about 100psi on the monarch shock where as a typical fork I may only loose 5 psi..

How are these suppose to get filled to 250psi on the nose if they loose 100psi when you remove the adapter?
 

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How do you measure that pressure after removing the valve? If you connect that shock pump again then air in IFP chamber will go in the hose and you will lose a lot of pressure. I suspect that the pressure that is released while you unscrew the valve comes from the shock pump hose and not IFP chamber. Remember that air volume inside a fork (or rear shock air spring) is much bigger than IFP chamber volume. That is why you lose different amounts of pressure.
 

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~Reformed Mechanic~
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2,177 Posts
Discussion Starter #9
Yes, that was part of the issue. For resolve, after I filled the chamber I threaded just the valve adapter in to see where the pin would depress I noticed that is was depressing the valve before the o-ring was completely seated and was loosing a tiny bit of pressure from the chamber. So I used a small drill bit to just just take a shaving or two from the center of the valve adapter, just enough so that the last half to full turn of the thread it was depressing the pin. This way I was not loosing anything when unscrewing...

Got it back together and Shock feels great, my only other concern is that its now filled with compressed air instead of the factory nitrogen. SRAM says this is okay to use but if it was just as good why would SRAM use nitrogen? Hopefully the moisture in the air wont be an issue :)
 

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Ok. The biggest "problem" with using air instead of nitrogen is that temperature will have bigger effect on pressure. Normally this is not a problem but if you do long downhill runs and shock temperature is increasing significantly then it is better to use nitrogen. There are some shocks that use air normally for IFP, for example Manitou Swinger, Fox DHX Coil and Air. So Nitrogen is better but if you can't get shock heated up significantly you shouldn't notice any difference.
 

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I use a slightly larger "O" made from "viton" than what comes on it , you should have an "O" ring supplier where you can go and try a selection until you have acoupple viton sizes you can take home and try . (the viton "O" rings are way tougher)

I have mine set up where it does not press on the valve when its installed, ( thats how they are supposed to work ) then when I hit it with nitro the pressure pushes the valve open and I see and adjust on my gage where I want the pressure and then I can dump the pressure off the back side and the valve seats and there you go .

These shock set ups really should have Nitrogen in them , and with a tank set up its way easier to fill.
 
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