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Joined
8/29/2010
Location
Grand Junction, CO
US
Edited Date/Time
9/28/2020 12:20pm
The question I'm posing: What are you more reliant on in your setup, the fork's spring or the fork's damper?
This may sound like a goofy question, with most people going "well, duh Brines, BOTH!". However, there does seem to be two schools of setup, with some opting for heavier, progressive, spring rate and wide open compression damping, others a bit lighter spring rate and more damping.
If you follow the FOX Dialed series, Loris touches on this a fair amount, as he seems to be looking to open things up and rely more on his spring. He also talks about Loic and Finn's setup, and basically says "how do I get that? Cause it looks amazeballs". (see below for what I'm talking about). He's talked about this further in other episodes.
Oh, and if you haven't figured it out by this point, we're talking compression damping, rebound is more personal preference and a byproduct of spring rate. You absolutely need it.
https://youtu.be/MEG870ckjPY?start=486
There are obvious technological differences between a spring and a damper, with the former being position sensitive and the latter being speed-sensitive. However, there is a crossover between the two. Say if you want to keep the fork up in its travel, you can add a few psi to the air spring or you can add compression damping. Using too much travel? You can add some high-speed compression or you can add a volume spacer.
The ride feel between the two adjustments is going to be different, but again, there is a crossover, especially with how easy it is to manipulate the modern air spring (progression, rate, etc).
When General Lee did his piece on data acquisition, they played with damping a fair amount. I do wonder how much of that could have also been accomplished with air spring manipulation?
There are a number of really fast industry guys I know that are running their stuff wide open on the compression front. After all, the vehicle we are supporting weighs 30-40lbs, not 200+ like a dirt bike or snowmobile.
Personally, I'm more apt to keep things as open as I can, mostly to preserve my hands and get the most grip in gnarlier terrain. Adding compression damping does give me more support, but it's at the expense of more feedback through the bar. The only exception being a smoother trail with eyeball sucking berms, where adding some low-speed compression can help.
In a perfect world, the first 20% of the stroke would be mostly free of compression damping, with speed-sensitive damping really being applied after the 1/3 point (position sensitive damping!). To add, damping would also be truly independent, with high/low speed, and no crossover between the two (as there is now...yes, there is).
Side note - Though I could have added rear shocks to the equation, too, I've specified front suspension as there is no leverage applied, frame to frame differential, pedaling, etc.
This may sound like a goofy question, with most people going "well, duh Brines, BOTH!". However, there does seem to be two schools of setup, with some opting for heavier, progressive, spring rate and wide open compression damping, others a bit lighter spring rate and more damping.
If you follow the FOX Dialed series, Loris touches on this a fair amount, as he seems to be looking to open things up and rely more on his spring. He also talks about Loic and Finn's setup, and basically says "how do I get that? Cause it looks amazeballs". (see below for what I'm talking about). He's talked about this further in other episodes.
Oh, and if you haven't figured it out by this point, we're talking compression damping, rebound is more personal preference and a byproduct of spring rate. You absolutely need it.
https://youtu.be/MEG870ckjPY?start=486
There are obvious technological differences between a spring and a damper, with the former being position sensitive and the latter being speed-sensitive. However, there is a crossover between the two. Say if you want to keep the fork up in its travel, you can add a few psi to the air spring or you can add compression damping. Using too much travel? You can add some high-speed compression or you can add a volume spacer.
The ride feel between the two adjustments is going to be different, but again, there is a crossover, especially with how easy it is to manipulate the modern air spring (progression, rate, etc).
When General Lee did his piece on data acquisition, they played with damping a fair amount. I do wonder how much of that could have also been accomplished with air spring manipulation?
There are a number of really fast industry guys I know that are running their stuff wide open on the compression front. After all, the vehicle we are supporting weighs 30-40lbs, not 200+ like a dirt bike or snowmobile.
Personally, I'm more apt to keep things as open as I can, mostly to preserve my hands and get the most grip in gnarlier terrain. Adding compression damping does give me more support, but it's at the expense of more feedback through the bar. The only exception being a smoother trail with eyeball sucking berms, where adding some low-speed compression can help.
In a perfect world, the first 20% of the stroke would be mostly free of compression damping, with speed-sensitive damping really being applied after the 1/3 point (position sensitive damping!). To add, damping would also be truly independent, with high/low speed, and no crossover between the two (as there is now...yes, there is).
Side note - Though I could have added rear shocks to the equation, too, I've specified front suspension as there is no leverage applied, frame to frame differential, pedaling, etc.
Poll
This was on a 150 pike with a Charger 1/debonair. Now on a Lyrik with Charger 2/debonair and it took me a little more puzzling to get to the same place. I tried the same set-up but felt like I needed too many tokens or was running absurdly high pressures to get the midstroke where i wanted. Formula Neopos spacers solved it though. I can run still high, but more normal pressures, get the mid-stroke, but don't feel like I hit a wall at the end of the travel like I did with 3 spacers.
Also, I imagine the way the stock damper is set up affects how this set-up approach works too. Seems like the Chargers work really well with no compression, but I've heard Fox is kinda the opposite. Again, haven't had much time on one so don't know if that's true.
I think a lot of Loris' comments about the other guys may reflect more on different suspension designs more so than tuning. Loic has been logging data for a long time now, and his riding style would make a hardtail look like butter over rough terrain. Probably not the best guy to watch while you figure out your own settings.
Good spring is cheaper than good damper. And I think spring is easier to understand (thus setup) for most users(for me at least).
Evol, Debonair, Luftkappe... Are all much cheaper upgrades for budget or older forks than Charger 2.1, Grip 2, etc..
I only ever rode cheap forks with one compression dial, which by increasing low-speed damping introduced a lot of harshness. Upgrading air spring to debonair helped to control the stroke as needed and I couldn't justify buying damper upgrade too.
Its harder with shock, because changing rates of linkage introduce new funkiness to the game. That's why there should be more ways of damper adjustment in the rear, to fine-tune this increased number of variables. I like to rely on spring, but sole 3 position compression levers on shocks are a joke.
But more on topic, spring has to be supportive but there's no substitute for good compression damping.
Interesting post.
Gone the opposite way lately to greatly results.
Formerly focused on spring via cutting tokens small changes to PSI (rockshox lyriks), and then turning in until the fork got harsh.
Now, and with much better results (Fox grip2), focuses on damper. Air spring full linear, enough psi to not bottom out too much, then really caring about 1 click at a time. landed on 2 clicks from closed LS, 7 clicks (of 22) from closed on HS, and rebound as slow as possible without packing up (ie 1 click less than hands go numb)
How do you balance adding HSC so that it holds you up but you still have grip through square edged hits?
In my experience I'm strong enough to hold onto the bike through the bigger stuff, as usually there isn't much of it on a run-of-the-mill enduro track. On the flip side there are countless hits of the small/medium variety.
Do you guys think adding HSC helps the fork ride higher through big holes? I always thought that was more of a LSC, unless the holes were more square edge. Even still, I've never added damping and thought "oh, now it feels good".
On the flip side, I've added pressure and found myself more in control as I have more available travel through smashy bits.
The budget oriented Fox and Marzocchi stuff outperforms just about everything (especially if you are more spring biased) and can be had new for around $500. That's awesome.
Thread derail, but that fork is the best deal going.
For me at least, I could only close damping (both R and C) so much before the fork would get harsh... so one less click than that.
But would have preferred more damping. Just couldn’t get there without numb hands
.... Adding Tokens/spacers have very minimal effect on the mid-stroke. They affect and are used for ramp up the latter third of the travel. If you add spacers and keep your pressure the same, it may feel like there is more mid-stroke support (there definitely is not less!). That said, the point of adding spacers is so that you can lower the air spring pressure and still prevent bottoming. So when you add spacers and say, drop 10psi, you just lost mid-stroke support in favor of it being more supple off the top and still resisting bottoming. A big negative spring + higher spring pressure is what creates good mid-stroke support.
Once Rockshox rollled out Debonair in their forks they were able to lower the number of tokens that shipped in the forks. Users could still have good off the top supple feel while running higher air pressures. Which meant more mid-stroke support and less likely to bottom.
He opened up my high-speed compression front and rear, opened up my rebound front and rear, both almost wide open, and added 7 psi to my fork. SEVEN, or about 10% more total pressure. The bike rode night and day better. It stayed way up in the travel when I braked, it tracked super smooth through chatter, and I felt like I could happily ride full speed into anything. I remember my bars felt like they were 4" higher. It was 100 times better. I still got smoked, but it was the first time I finished a World Cup quali with a clean run. It changed the way I set up bikes.
TEAMROBOT how much was your damping off? I would guess more than 10%. It does like there is pretty narrow sweet spot with suspension
Unfortunately there was little to no information from BOS how their air spring works, but it seems they very much were able to get coil like support through high air pressure and a large negative spring chamber. Mind you, these forks didn't have no possibility to get spacers in there!
I have never ridden a better air spring to this date. The fork also had a hydraulic bottom out damper to control the end stroke, which saved my ass on several occassions.
Now I am back on coil and seriously considering it for my trail bike aswell.
Like Robot said, a good tuned spring to me is the most important thing. Damping is there to control it and balance front and rear.
I usually have the best experience with 15-20% sag and relatively open compression damping.
'wide open' does not mean no damping, it just means the least restrictive end of whatever damping range is available in your fork/shock. If you really want to know what wide open feels like take your fork cartridge out, but good luck trying to ride on anything but pavement.
The best damper in the world cannot correct for a poorly set up spring.
You really do want to be using your available travel, but that doesn't mean bottoming out a specific number of times.
'mid stroke support' seems to be a catch-all term that also includes not enough air pressure, too little LSC damping, too much rebound damping, bars too low.
Many people run their rebound too slow
poor front wheel traction can actually be a rear suspension issue
As terrain gets steeper your bike's effective reach measurement increases and stack decreases making the front end feel lower and farther away. Don't rely on your suspension to get your bar height where you want it, instead try raising the bars (*using higher rise bars to raise your hands instead of stem spacers won't shorten your reach).
Air springs are naturally progressive. In a 160+ travel fork you likely don't need a stack of tokens.
In simplified terms suspension setup is a balance of comfort (feedback), traction (grip), and stability (control). You can't have all three at all times
If you are a slower to average speed rider, it might not be such a great idea copying the settings for a faster more aggressive rider.
balance the front and rear. Unbalanced spring and damping setups make both the fork and shock feel worse even if one of them is properly tuned.
Personally, I start with spring rate front and rear (starting with the front) and then rebound front to rear. Next would be LSC front to rear, and last would be HSC. Generally I feel like my control of the bike begins with the fork and then it's a matter of tuning the rear shock to match, but again that's just a starting point.
Get a good digital pump. +\-2psi is noticeable so you want to set pressure as exactly as possible
Some forks/bikes sag under their own weight and it’s not the same every time. Compress the fork/shock several times to equalize the chambers and set pressure with the wheel lifted off the ground for consistency.
Tires are part of the suspension equation and will start to compress before the fork/shock. Have you tried lower pressure?
A spring is something very dynamic. It resists compression by force, but as soon as the compressing force is greater than the resistance of the spring (at any point), the spring will start to compress. That means that if you have a compression event (say you run over a big rock at high speed), the fork will compress violently and if the spring rate is more or less correct, the spring will compress accordingly. Any remaining force will be transmitted to the bike and subsequently to the rider. There is very little inertia in this system, just the unsprung weight (wheel, fork lowers), a bit of friction, and that's it. Left to its own devices, a spring will always feel great on that initial hit, as it can compress as fast as need be to get out of the way without transmitting too much force to the bike/rider. A spring is also position-sensitive, meaning that resistance increases as the spring is compressed. That means that the deeper into travel you sit, the harsher the fork will feel, all other things being equal. An air spring is inherently more progressive than a linear coil spring, which is one reason that air forks don't quite have that "coil feel" (the other being stiction and something about the dynamics of what happens when you compress gases quickly).
Damping on the other hand, is very different. Damping is basically about forcing a liquid to flow through some kind of restricted passage (an orifice of a certain size, or a shimstack with a certain stiffness). Such a system is inherently not very good at getting out of the way quickly. The reason is that damping is more time-sensitive, whereas a spring is more force-sensitive. In other words, it takes a certain amount of time for oil to flow through a hole of a given size, and pushing violently against the oil isn't going to change that all that much (the aforementioned rock you just rolled over). That is why a fork will feel stiffer and stiffer as you slow down the compression damping. Of course the high-speed compression circuit is there to allow oil pressure to blow off more quickly than the low-speed damping circuit will allow, and on some higher-end forks you can even adjust the two independently, which is where things get a bit tricky (the two circuits are often billed as independent but in reality, there is always some level of interdependence). Setting up your compression damping involves balancing the need for extra hydraulic support of some kind against the need for comfort and/or control, but the basic principle of how hydraulic damping works will always translate to some degree of harshness when you slow down the damping.
Suspension companies are great at selling their new and improved dampers, but for my money, the big change over the last two years has been the introduction of the larger negative air chambers and much improved design of the overall spring rate curves. It is now possible to get very close to that perfect mix of softness and support, with just a touch of damping needed to fine-tune the behavior of the suspension to suit your taste and riding style. "More" or "better" damping doesn't inherently feel better, I for one am always looking for ways to run as little of it as possible (and as Lee already mentioned, "fully open" doesn't actually mean there is no damping, it just means you're at the end of the adjustment range the manufacturer chose to give you access to).
I do feel that the compression tune is a bit heavy now (running quite low sag ~15%) and don't feel the same need to pile on LSC to stop the fork wallowing between sag and end stroke with the increased mid stroke support.
It seems a little counterintuitive, but I've gone from a progressive spring setup to linear, and actually want less damping. How about that?
https://www.vitalmtb.com/features/MTB-Suspension-Q-amp-A-Session-Darren…
Lots of relevant discussion to this particular topic is in there coincidentally. Nerds rejoice hahaha
I spent a lot of time on the phone with Fox when I got my new 36 to fix an issue that I was having. Over the course of remedying that issue we talked a lot about setup and really working with the air spring as others have mentioned. They continually expressed to me you need to focus on the spring and rebound before you do anything else and its made a world of difference.
As team robot mentioned, I ended up losing a volume spacer running 6 PSI more air and two clicks faster on the rebound than I normally would. 6 PSI doesn't seem like a lot but on % basis it ended up being around 8% more air which isn't trivial especially at the end of the stroke (Can't recommend a good digital pump enough). This has made an enormous difference in high speed chatter, which Fox said is where your "mid stroke" is. I have way more control/comfort, can push the front end more, and gives me better traction.
On the compression side, I am running 3 clicks less than baseline setup. However, I do play with the compression a fair bit based on the trails I am riding. I have a classic flow trail that is really smooth (outside some high speed small bump sections) right next to my house and is my quick hitter trail. On that I run two more clicks of LSC which gives me the feel I want with pumping and what not vs. on a more DH/Enduro ride I back off those two clicks of LSC and add one click of HSC which gives me a touch more support on drops and jumps.
Once I got the air spring dialed, it was a lot easier for me to feel how compression impacted the ride for me. Before, it was a lot harder to tell what the compression was doing in terms of feel for me.
As the DVO Onyx 29r is still a month or more away I'm using a boxxer wc debonair and really struggling with set up. If I use the lowest recommended air pressure for my weight and 0 clicks in on both lsc and hsc it maintains ride height but feels harsh on the little bumps and in corners while feeling good on the big hits (though it only gets about 180mm of travel with no tokens). If I lower the pressure and add 2-4 clicks of lsc it corners well but dives on steeps and under braking (but does use all 200mm of travel once in a while).
Miss my DVO!
For reference, the compression setting baseline was 6 out of full in on LSC and 10 out of full in on HSC. 2 out on LSR, 3 out on HSR (I think)
I'm 16 out on HSC (full open), 11 out on LSC (one click in from full open). High speed rebound 4 out, low speed rebound 5 out.
I have 94psi in the spring. Zero volume spacers. 170mm.
I'm around 195lbs in the birthday suit.
Just figured throwing my settings into the thread might help.
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