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Discussion Starter · #1 ·
I love my bike, best I've ever owned, 2013 Rumblefish using RS Revelation 120 and Fox CTD DRCV 120. When I got set up at the dealer he said with normal weight on the pedals the stanchion indicator ring should only be up maybe 20% from the seals. He said mess around with it on a few rides, play with the adjustable lockout and rebound and the ring should end up just short of the top of the stanchions. After several rides and several shock pump adjustments I can't seem to keep from pushing the ring to the very top. I'm afraid I'm bottoming out or potentially causing internal damage by using all of the travel. I weigh 170 and with gear 175ish so I have the fork pumped to about 115 psi per the manufacturer's specs. I see the same issue with the shock when it is in Descend mode. Do I need to pump it up way more? I'd like to have both shock and fork wide open and hit some drops but still keep from using literally every mm of travel.

Thoughts?
 

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It's not a bad thing to use all of your travel, the damping typically increases late in the stroke to slow it on bigger hits while keeping it plush over rocks and roots. Can you actually feel it bottoming, where you feel it in your wrists or hear a clunk, or are you just looking at the o-ring.

The psi numbers are just guidelines to get you close, you're going to have to tweak it for your riding style and setup. If you don't have a pump you could have the shop set it higher than you know you want and then bleed it off slowly during test rides until it feels right. Be careful there's not much air in them, if you hold down the valve all the way for even a split second all the air will be gone.
 

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Sometimes the difference in dampening adjustments can be very minor with significant results. I haven't worked on that model of Fox fork, but on some of the ones with external compression adjustments the difference can be as subtle as one or two clicks between wide open and almost rock. It sounds like you need more compression dampening either from the valve adjusters(external) or oil viscosity change(internal). Since it is a feel thing, try taking it back to the selling shop and have him give you a walk through. Try air pressure a little, but be conservative.

If that doesn't correct the problem then it would possibly highlight another course of action. It should not use up a significant portion of travel unless you are in a very rough situation.
 

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Discussion Starter · #4 ·
I don't hear the 'ping' associated with bottoming out and my teeth are not grinding so.. The bike came with the Bontrager pump so I've messed with it a bit at home. I will pump higher than I have before and test it to see. Speaking of that, how long is a reasonable amount of time for the air to naturally decrease? After only a few weeks of riding each time I plug the pump back in it is maybe down... 5-10 psi than before? Meaning I set to 115, ride a few times over a week and check again and it's nearer to 105. Is that normal?
 

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At 20% sag, it shouldn't be bottoming out. Your dealer is correct about where the o-ring should ideally end up after an average ride.

I only use the pressure # as a point of reference so I can duplicate what works. Most manufacturer recommended settings are too high IMHO. For me, I prefer closer to 30% sag, and sometimes a little over that to get a smooth ride, yet not bottom out. But that is for me.

If you're bottoming out, I would keep adding air until you don't and then see how the rest of the ride has been affected and whether or not you like it (and then go forward from there).

The shock pump will naturally be 5-10 psi lower when you take the next reading because of the air it takes to fill up the pump when you reconnect it.
 

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Discussion Starter · #6 ·
ok, thanks everyone. Sounds like I need to pump up higher than I thought before and see how it performs. I'm not doing any free-ride/downhill but it is not uncommon for me to be 2 feet of the ground. I'm looking for the proper setting to absorb that impact with both shock and fork set wide open yet not push the O-ring to the top. Should I instead be dialing back the lockout a couple clicks from open to stiffen up front and cheat? I feel like this is avoiding the issue. I guess I would like the suspension to be as soft as possible for a 2 foot drop yet leave the O-ring 5mm from the top. 130 psi? 150?
 

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I'd run the lockout wide open for now. IMO, you shouldn't have to use that to keep from bottoming out. I would only use that to firm up the ride while climbing. JMHO.
 

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I can't remember the details, but I recall something a little tricky about setting up a DRCV suspension. be sure to look that up and make sure you're doing it right. the DRCV system basically has a secondary air chamber in it and if you're not pumping it up correctly, it won't work right.
 

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Also worth a mention, one of the LBS mechanics I talk to about stuff suggested to set your pump up pressure aprox 5psi higher than you want it to be as the "take off" of your pump from shock will loose just a touch of pressure..so I do that as it sounds feasable...
 

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Also worth a mention, one of the LBS mechanics I talk to about stuff suggested to set your pump up pressure aprox 5psi higher than you want it to be as the "take off" of your pump from shock will loose just a touch of pressure..so I do that as it sounds feasable...
I wouldn't go as high as 5psi. Shock pumps are designed not to lose a bunch of air when you remove them. Maybe 1-2psi, at most. I don't do any at all, and honestly don't think you need to add ANY extra. The "hiss" you hear when removing the pump is the pressurized air escaping from the pump itself, not the shock. The "loss" of pressure you see when you reattach the pump is the air from the shock filling the pump.
 

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Try the 60% rule and take it from there. Calculate 60% of your weight and make the result the psi's to be pumped, ride it and adjust as needed.

20% sag is good but some people like a softer suspension so they give it a bit more.
 

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Discussion Starter · #13 ·
Again, thanks for all the input here. Jeffj, I plan to pump it up extra a bit on my next ride and examine it after a normal descent with both wide open. Mack Turtle, I think what you're referring to with the DRCV is the secondary chamber. The tech showed me when screwing on the pump it will show pressure but to continue screwing on the pump and when it opens the second chamber the pressure on the guage will increase again. At this point you are showing a true reading. Mofoshoe Im pretty sure it is a Revelation RL.
 

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I wouldn't go as high as 5psi. Shock pumps are designed not to lose a bunch of air when you remove them. Maybe 1-2psi, at most. I don't do any at all, and honestly don't think you need to add ANY extra. The "hiss" you hear when removing the pump is the pressurized air escaping from the pump itself, not the shock. The "loss" of pressure you see when you reattach the pump is the air from the shock filling the pump.
Yeah makes sence..thanks. I wasn't trippin too hard on what my PSI is. I too go more off of feel more than what the guage says..I am only 30days old with a real air fork so = GEENHORN!!!!! LOL
 

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You should be using all of the travel on your rides,that means bottoming out once or twice.Set the sag around 30% and go from there.
I am going to have to disagree with that. There are rides that I go on that I will be sacrificing efficiency if I was just trying to blow through all my travel each ride.
At the same time, you want to be able to use the travel that you are given if the terrain is difficult enough(downhill/very techy terrain).

OP, do you feel like you are lacking low speed compression or compression in general?
 

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Discussion Starter · #17 ·
I feel like the suspension, fork more so than shock, is using its travel too effortlessly. I have a general understanding of how it works and the only simple conclusion I can come to is I need to add more air than I thought to achieve the correct compression.
 

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At 20% sag, it shouldn't be bottoming out. Your dealer is correct about where the o-ring should ideally end up after an average ride.

I only use the pressure # as a point of reference so I can duplicate what works. Most manufacturer recommended settings are too high IMHO. For me, I prefer closer to 30% sag, and sometimes a little over that to get a smooth ride, yet not bottom out. But that is for me.

If you're bottoming out, I would keep adding air until you don't and then see how the rest of the ride has been affected and whether or not you like it (and then go forward from there).

The shock pump will naturally be 5-10 psi lower when you take the next reading because of the air it takes to fill up the pump when you reconnect it.
^^^This. I much prefer 30%+ sag. 20% seems too little negative travel for me.:) It's ok to bottom out a few times each ride, as you are using full travel. if it happens too many time a ride then add more air or compression.
 

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I feel like the suspension, fork more so than shock, is using its travel too effortlessly. I have a general understanding of how it works and the only simple conclusion I can come to is I need to add more air than I thought to achieve the correct compression.
The knob on the top of the fork adjusts low speed compression. I believe it has 6 clicks between fully open and fully locked out. I usually run mine between open and 3 clicks depending on terrain. This prevents bob, brake dive, etc. but allows you to take big hits/rocks/high speed stuff just fine.
 

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Discussion Starter · #20 ·
That is what I have been running also to try and moderate how easily the fork can use all of the travel. I'm still finding that on some larger drops my fork is still using all of the travel. I'm going to pump it up higher and leave it wide open and see how it performs. Then after it loses a few psi click over a few on that knob to see how it performs.
 
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