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Discussion Starter · #1 ·
I just completed a rebuild of my '12 RS SID RL dual air. This project was instigated by decreased performance.

In particular, at the beginning of each ride, the first 3-4 times I lifted the front wheel up (over a curb, for example), the fork made the classic flushing/whooshing noise. After the first few times, the noise stopped for the remainder of the ride, and would occur again at the beginning of the next ride.

A few data points: I've searched the forum for this specific issue, and haven't found anything; I followed SRAM's recommendations re: oil levels to within +/- 1 ml; all o-rings were replaced during the rebuild; and I inspected the original damper very closely and decided not to replace it, as it looked to be in great shape.

To the point: post-rebuild, the fork's performance is vastly improved, but the same noise phenomenon exists: lift front wheel at start of ride, hear noise, repeat 3-4 times, noise disappears for rest of ride.

I'm fairly/almost totally certain this noise is down to oil flowing through the damper; what I can't figure out is why it occurs only at the beginning of a ride: pressure is obviously equilibrating somewhere, but where? And is this indicative of a fuc#ed damper? Too much/too little oil? Some other issue?

Much gratitude in advance for all input!

Jeff
 

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Do you store your bike hanging up or anything other than level? One way or another because it is an emulsion damper (oil and air mix) there might have been oil sitting on top of the compression piston that had to mix in back in. It's not a major problem but you can try raise the oil level about 5mm at a time to see if it helps. As long as the cartridge can easily be cycled through its whole stroke you can add more oil. Sometimes the recommended levels aren't always accurate.
 

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Discussion Starter · #3 ·
Do you store your bike hanging up or anything other than level?
Hi, Johnny-

Apologies for not having responded sooner: I sincerely appreciate your perceptive, knowledgeable response. Indeed, my bike is stored horizontally (lives in my car), so I'm sure that's an issue. I'm going to add 5ml fluid per your recco and see how it goes.

Much gratitude for your help,

Jeff
 
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