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Question about Rockshox SuperDeluxe spacer install and SAG/PSI

1079 Views 2 Replies 2 Participants Last post by  TheNewestOf Guys
So I have an evil with a Rockshox Super Deluxe RCT Debonair and I felt like I was going through the travel on big hits a bit too easy. So I decided to install a single spacer and see if that improved things. Everything went off without a hitch but now I am noticing that in order to get 30% sag I am having to lower the PSI by almost 10 which seems like a lot. From my reading and basic understanding I thought the PSI would be about the same with only a bit more ramp at the end and now I am worried I did something wrong.

I made sure to cycle the shock from no air to full air cycling it 5x at every 50psi to make sure there is air in the negative. I have done this 3x now since I am a bit anal. I did not add any oil to the can when I put it back together and I am wondering if I should have done that. It's snowing, trails are closed, so I can't ride it so I am just looking at it hoping I didn't do anything wrong.

Pre spacer, single spacer, it was 180psi and according to O-ring just shy of 30% sag with spacer I am at 171 and just shy of 30% sag so about a 5% difference in pressure.

Let me know if I have to do it all over or if I missed something. I might just knock out the 50 hour service since working on the shock seems pretty easy.

I know there are a few Shockwizards on this forum so I am hoping to tap into that knowledge. And I am having hard time dealing with this Rockshox and might just switch to coil but I am still new enough to not know if this is a Me/setup thing or shock thing.

I did reach out to SRAM about this but I haven't heard back yet so I figured I would ask around.
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So when you install a volume spacer your essentially changing the volume of the positive side of air spring. So now that the space is smaller your PSI# for any given sag has also become smaller. So if you add another vol. spacer you will have decreased the volume again which will again decrease the amount of air you have to put in the shock to get the same 30% you had originally. Hope that helps. Also, check Shockcraft's website which has a really good explanation of how volume spacers are supposed to be used.
I have read that site and many others and I think I honestly read too much, there is definitely some conflicting bits of information out there. Most were saying measure Airpressure insert spacer return to same air pressure and ride. I have always measured sag so when it was different I got worried. I am in the south east so I cannot ride due to it being a winter wonderland and everything is closed. I guess I was just not expecting such a large change in air pressure for such a small add on.

I do appreciate the info!
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