Another factor in all of this I keep coming back to - if your fork hasn't been serviced much, stiction acts like some really crappy LSC.
If there is one thing I absolutely hate about modern suspension, its how easy it is to contaminate the lowers. Frequent service, though easy, is annoying, and just as important as lubing your chain or similar. Why is it not as easy as lubing your chain?
Part of the problem is the inherent design of "right side up" forks. I'd be very willing to go USD and take 1.5 pounds. Yeah they are 'flexy'. I think this is blown way out of proportion.
Alternatively, Fox has a patent on a really cool oil re-circulation system that will help keep oil around the seal, and going through all the bushings.
Regardless, I could see adding more damping if the bushing/stanction interface was likely to stay smooth sliding, and we eliminated how much bushing bind we get when twisting the fork.
I read somewhere from someone smarter than me, "Spring controls the mass, while damping controls the spring"
I've always thought of compression damping as slowing down a fork's movement to it's spring balance point. And I want the fork to move as fast as possible in response to fast, square, edges. I use my arms a lot for travel as well and that is where I exercise control. So I am more of a spring/open damper rider.
I read somewhere from someone smarter than me, "Spring controls the mass, while damping controls the spring"
I've always thought of compression damping as slowing down...
I read somewhere from someone smarter than me, "Spring controls the mass, while damping controls the spring"
I've always thought of compression damping as slowing down a fork's movement to it's spring balance point. And I want the fork to move as fast as possible in response to fast, square, edges. I use my arms a lot for travel as well and that is where I exercise control. So I am more of a spring/open damper rider.
Good quote.
I also wanted to point out, we are on mountain bikes where the body can handle so much more of the impact compared to say, a dirt bike or (obviously) a RZR, UTV, baja truck etc.
That's a lot of the equation that has to be tricky as hell to balance out. I will literally put my face into my handlebar on my dirt bike if I over jump something without adequate damping. Mountain bike, usually its on me to BMX through the event (BMX guys have zero travel and make us look like wusses 99% of the time when it comes to "big hits")
Like I mentioned earlier, most people don't have what I'd call "big hit" type of terrain over and over, its more roots, square edged rocks, etc with maybe one huck to flat or questionable double on the entire track. To tune for this one huck seems like putting 35s on your Chevy just to drive down the highway 99.9999999% of the time.
I couldn't agree more. I bought a new take off 36 Grip fork for $500. Took no time to set up and it's amazing. Easily the...
I couldn't agree more. I bought a new take off 36 Grip fork for $500. Took no time to set up and it's amazing. Easily the best fork I've ridden. I wouldn't want all those dials on the Grip 2 to worry about.
Not sure if the rumor is true, but word was the Grip stuff was working so well, with product testers going "gimmie that Grip 1, leave that FIT stuff on the shelf" that Fox took the IFP damper and made it into something "high end" with more adjustments.
True or not, that Grip 1 is no slouch of a product.
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep...
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep trying to like their suggestion, as if I'm missing something, but I keep going back to slightly more air, and a lot less damping.
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.
Yeah Brines. I am off them a bit as well.
Although I am running less Air then recommended, a volume spacer, and faster rebound on a 160 then my weight recommends. I'm 185 with 72 PSI, 7 LSR, 4 HSR, 15 HSC and 11 LSC as base settings and then adjust compression as needed.
FWIW, the Fox told me those settings are ball park and not to pay much attention to them. Setting sag, rebound based on a quick hit and release to see if the tire skips, and then rolling bunny hop to check volume (80% of travel) is what should be your starting part. Then adjust from there based on ride experience. I actually think Jordie does this in one of the dialed episodes.
I'm in a comparable boat with my 36 RC2, which is actually the biggest reason I haven't done the Grip2 damper upgrade.
I'm 155-160lbs with 61psi, one token, HSC 2 clicks from fully open, LSC 5 clicks from fully open, and rebound as fast as I can get it based on the tire-staying-on-the-ground test (5 clicks from fully open).
When I first got my bike, I set the fork up close to Fox's recommendations, went to a gnarly enduro race (unfortunately the bike was backordered, and I didn't get it until the weekend before the race), was beaten to death because of the compression settings, drove the whole way home pissed, rented a Shockwiz, was implicitly taught how to set-up suspension with a mini computer and an app, and have been pretty stoked on my bike ever since.
Interesting to note that I raced two races in a four week period without and then with proper set-up, and, compared to the fastest pro who attended both races, I went from 14% back (10% back when removing a stage where I had a big crash) to 2.3% back. Likely had a lot to do with getting comfy on the bike in general, but I tend to think suspension set-up played at least as big of a role.
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep...
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep trying to like their suggestion, as if I'm missing something, but I keep going back to slightly more air, and a lot less damping.
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.
160lbs 180mm travel. No spacers 65psi 10 lsc, 14 hsc, 6 out on both rebounds. If it gets steep I'll add a couple lsc. If its fast with big hits I'll add 1-2 hsc. So yeah the base settings aren't too far off for pressure and rebound. If my local trails were faster and steeper I would probably run 68-70 psi as fox recommends.
Went from running a progressive air spring setup (pike + 2 tokens) to a coil conversion (w/o end stroke adjustment) with a comparative bottom out force...
Went from running a progressive air spring setup (pike + 2 tokens) to a coil conversion (w/o end stroke adjustment) with a comparative bottom out force. I'm consistently using more travel, still never bottom out harshly and have far more grip than before - without that feeling of riding along on an invisible wall of volume spacers I had previously (the ramp up from 2 spacers was harsh enough that it almost felt like I was bottoming with another inch of travel left).
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?
Same experince her. I even got the smashpot with bottom out control, and i dont use ut B/C the spring feels really on the sweetspot (only on big hits, f*Ups in rock gardens) that i use full travel.
The experince of the linear setup with a coil in the front, makes me wonder about a coil setup in the back. I dont have to most progressive frame(cube stereo 150) but from what i feel in the front, i really want to Try. The support from the beging stroke is tempting..
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep...
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep trying to like their suggestion, as if I'm missing something, but I keep going back to slightly more air, and a lot less damping.
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.
I did find that I could start leaving the damping settings more towards the middle of the range with GRIP 2, whereas on RC2 I'd have it all pretty much open. Now I can "get away" with more damping with the GRIP 2 (closer to FOX's baseline), but that still doesn't mean I always want to. With the EVOL air spring offering better small bump compliance AND more support, I don't need all that damping, but it's good to know it's there when a particular trail demands something very different. I would typically run one spacer and a bit less pressure than you as well. I think. I'm currently doing a bunch of testing with the latest Ohlins fork, swapping between coil and air and all kinds of fun, so I don't quite remember where I was on the FOX last time I rode it.
Tyre pressure is the first thing you should have dialled, then make sure your fork is in good working order and sliding properly on its seals and bushings. Even a slightly sticky fork can be the difference of 5 to 10 psi or the last 20mm of travel alone!
Spring rate is the most important thing to get set up, it's what supports your weight and pushes the wheels back to the ground so has the biggest effect on how the bike responds to bumps. The damper dissipates the "left over" energy to help the spring use only the travel it needs to, putting in a simple way.
On the topic of damping though, it is wrong to think that adding compression damping automatically means you a "restricting" your suspension or adding harshness, it is there to absorb energy so everyone needs a certain amount of that, which varies depending on the speed and aggression you ride at. Don't be scared of it! I'm not saying everyone should be running loads of it, but every brand has wildly different ranges of adjustment so running your adjusters open could mean you are so far off the end of having barely any damping that it becomes harsh again.
Tyre pressure is the first thing you should have dialled, then make sure your fork is in good working order and sliding properly on its seals...
Tyre pressure is the first thing you should have dialled, then make sure your fork is in good working order and sliding properly on its seals and bushings. Even a slightly sticky fork can be the difference of 5 to 10 psi or the last 20mm of travel alone!
Spring rate is the most important thing to get set up, it's what supports your weight and pushes the wheels back to the ground so has the biggest effect on how the bike responds to bumps. The damper dissipates the "left over" energy to help the spring use only the travel it needs to, putting in a simple way.
On the topic of damping though, it is wrong to think that adding compression damping automatically means you a "restricting" your suspension or adding harshness, it is there to absorb energy so everyone needs a certain amount of that, which varies depending on the speed and aggression you ride at. Don't be scared of it! I'm not saying everyone should be running loads of it, but every brand has wildly different ranges of adjustment so running your adjusters open could mean you are so far off the end of having barely any damping that it becomes harsh again.
I totally get this in theory. I keep trying to make it work, but I find the bike doesn't track super well through square edged stuff, which is where I *really* need my suspension working well to keep my upright.
Push's Mr. Murphy too touched on this. Going firmer to make it feel softer...
This was the other part of me putting up this thread, as I understand all this in theory, it just doesn't seem to pan out in practice. Likely, because I suck.
Very good topic and good discussion. This is something I've done a LOT of testing on.
I've built myself a franken-36, Just stuff I had laying around combined with a purchase of a Grip2 damper, it's impressed me but I think there is a bit more work that can be done.
36 Rhythm CSU and Stantions. (44 offset)
36 Factory Lowers (29 inch)
Grip2 Damper
Vorsprung smashpot at 170mm with 55lb spring, hydraulic bottom out
SKF seals
I tossed and turned between a 50 and 55lb spring with damping added to suit the lower spring rate. In the end I preferred the 55 with basically no damping at all and a pretty quick rebound.
Interestingly, the grip2 isn't night and day better than the FIT-GRIP. I'd probably save my money if I was to do it all again. Very good and underrated damper.
I spent a bunch of time on this recently so I'll add my 2 cents. Disclosure: I work at PUSH.
Lee had some pretty good bullet points and I'll echo some things already mentioned above.
The spring should set your ride height (i.e. sag) and control your bottom out. You shouldn't really ask it to do much more than that. It gets complicated because of the ratio of sprung mass to friction in mtb forks. The added stiction can throw off setting your ride height, but getting the spring dialed is the first step to a proper set-up.
On to the damping... First that same friction adds damping and it can be a significant percentage compared to the actual damper. Plus, this force can be position sensitive due to chassis flex, internal alignment, etc, etc. Bottomline, you might have the compression “wide open” because of the added friction in the system. (Take some time in a parking lot to adjust the tightness of your thru axle, you might be surprised how much friction it can add.)
The other issue on most mtb forks is the shimmed HSC circuit is progressive in nature. The progressive damping is decent for big hits but really lacks in chassis dynamics (i.e. staying higher in the travel). I haven’t listened to the pod cast yet but it was mentioned above, if you’re staying higher in the travel it can actually feel softer since you’re at a lower spring rate/ less progressive area.
Overall, fork set-up preference varies by rider more so than shocks and combine that with manufacturing tolerance is hard to get a small window that works for everyone. -Matt
Tyre pressure is the first thing you should have dialled, then make sure your fork is in good working order and sliding properly on its seals...
Tyre pressure is the first thing you should have dialled, then make sure your fork is in good working order and sliding properly on its seals and bushings. Even a slightly sticky fork can be the difference of 5 to 10 psi or the last 20mm of travel alone!
Spring rate is the most important thing to get set up, it's what supports your weight and pushes the wheels back to the ground so has the biggest effect on how the bike responds to bumps. The damper dissipates the "left over" energy to help the spring use only the travel it needs to, putting in a simple way.
On the topic of damping though, it is wrong to think that adding compression damping automatically means you a "restricting" your suspension or adding harshness, it is there to absorb energy so everyone needs a certain amount of that, which varies depending on the speed and aggression you ride at. Don't be scared of it! I'm not saying everyone should be running loads of it, but every brand has wildly different ranges of adjustment so running your adjusters open could mean you are so far off the end of having barely any damping that it becomes harsh again.
I totally get this in theory. I keep trying to make it work, but I find the bike doesn't track super well through square edged stuff...
I totally get this in theory. I keep trying to make it work, but I find the bike doesn't track super well through square edged stuff, which is where I *really* need my suspension working well to keep my upright.
Push's Mr. Murphy too touched on this. Going firmer to make it feel softer...
This was the other part of me putting up this thread, as I understand all this in theory, it just doesn't seem to pan out in practice. Likely, because I suck.
You're not wrong, it isn't going to be the same case for everyone. One problem is a lot of adjusters don't work very well, ie the LSC will make a huge change to the overall damping or do next to nothing for most of the clicks then suddenly ramp up the damping considerably for the last few clicks. Or something like the Fit4 cart has very soft high speed compression but the design of the valve means it gets harsh very quickly when adding lsc. Most people then assume the fork is "overdamped" when really its just a limitation of the damper and why Vorsprung made the Fractive kit.
Also its been mentioned a few times now but if there is too much friction then you might already have harshness present and adding compression is obviously not going to help that.
Just listened to the pt 2 of Darrens podcast and its a great listen!
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep...
One follow up question for those running the GRIP 2 stuff. Are you even close to what Fox suggested as their baseline? I'm not. I keep trying to like their suggestion, as if I'm missing something, but I keep going back to slightly more air, and a lot less damping.
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.
Cheers, would like to jump in your topic, cause i am a suspension nerd too.
i have a trek slash with a 160mm grip 2 fork
my actual setup: 1 spacer 82 psi, 8 lsc 14 hsc and 4 hsr 5/6 lsr. at the moment 5 lsr caused by higher temperatures.
x2 on the back with 220 psi, 14 hsr 16 lsr 15 lsc and 14 hsc, full on spacer. the pressure is higher than normal caused by the longer shock stroke 60mm (standard is 57,5mm)
measured sag (standing, not sitting) the front is nearly 16% and the back 28%. full travel front only when i nearly die on a huck to flat, full travel back more often. tyre pressure 1.65 front assegai DH and 1.9 back aggressor DD.
my bodyweight is 82kg naked
i would describe it as an active setup, good grip and small bump on flatter trails. really nice balance for flat cornering.
if i really push into big compressions i feel that it lacks compression - bouncing through travel. but again a really good setup for riding playful.
on steeper trails like 15-20% drop, i really feel that the front end is to low (when breaking) to ride aggressive. i like it to break hard on my breaking points and not be dragging to much. in this moments i feel that i need more support. i fiddle around with compression on the front but could not find a sweet spot. if i close for 1-2 clicks on lsc/hsc i am immediately loosing grip cause the tyre tracks the ground way less when it gets flat again....?
dont know if i can get a better overall feel with more/less psi, more/less rebound oder compression. also the back of the slash is packing down if i have to break hard. rebound is already fast. maybe i have try to close compression to ride higher in the travel..
I spent a bunch of time on this recently so I'll add my 2 cents. Disclosure: I work at PUSH.
Lee had some pretty good bullet...
I spent a bunch of time on this recently so I'll add my 2 cents. Disclosure: I work at PUSH.
Lee had some pretty good bullet points and I'll echo some things already mentioned above.
The spring should set your ride height (i.e. sag) and control your bottom out. You shouldn't really ask it to do much more than that. It gets complicated because of the ratio of sprung mass to friction in mtb forks. The added stiction can throw off setting your ride height, but getting the spring dialed is the first step to a proper set-up.
On to the damping... First that same friction adds damping and it can be a significant percentage compared to the actual damper. Plus, this force can be position sensitive due to chassis flex, internal alignment, etc, etc. Bottomline, you might have the compression “wide open” because of the added friction in the system. (Take some time in a parking lot to adjust the tightness of your thru axle, you might be surprised how much friction it can add.)
The other issue on most mtb forks is the shimmed HSC circuit is progressive in nature. The progressive damping is decent for big hits but really lacks in chassis dynamics (i.e. staying higher in the travel). I haven’t listened to the pod cast yet but it was mentioned above, if you’re staying higher in the travel it can actually feel softer since you’re at a lower spring rate/ less progressive area.
Overall, fork set-up preference varies by rider more so than shocks and combine that with manufacturing tolerance is hard to get a small window that works for everyone. -Matt
Thanks for chiming in!
I'm not sure I agree with the bit about spring only controlling ride height and bottom out, but this is exactly what I wanted to talk about.
Considering the nature of a modern air spring, and how adjustable it is with respect to volume, pressure and to some extent negative spring volume, it seems we can tune this, too, add support (or not) where we want it. Its not something we can fully manipulate, but we can do so to a much larger degree than we could a decade prior.
On that note, I'm shocked (no pun intended) we haven't seen progressive coils in a fork. I know, space limitations, but yeah, a semi-related side point.
I touched on the bit about friction's impact on the overall fork's performance earlier, and I really believe this is a huge variable on all of this. I pointed this out way back when the Pike was released, but bushing bind is one of the biggest issues I see with current fork design and literally nobody is addressing it. The fork has substantially more friction going through its stroke when a twisting force is applied than when cycling in a centered fashion. Obviously, heavier riders are more prone to experiencing this than lighter riders. Another reason an USD fork that allows a little flex to keep things cycling straight may actually be a good thing...
When you say "progressive nature" with respect to HSC, are you suggesting it is position sensitive? Not really following there. I always thought if you were too light on your LSC, you'd run into your HSC too quickly, making it feel firmer, though it has nothing to do with where you are in the travel...
You're not wrong, it isn't going to be the same case for everyone. One problem is a lot of adjusters don't work very well, ie the...
You're not wrong, it isn't going to be the same case for everyone. One problem is a lot of adjusters don't work very well, ie the LSC will make a huge change to the overall damping or do next to nothing for most of the clicks then suddenly ramp up the damping considerably for the last few clicks. Or something like the Fit4 cart has very soft high speed compression but the design of the valve means it gets harsh very quickly when adding lsc. Most people then assume the fork is "overdamped" when really its just a limitation of the damper and why Vorsprung made the Fractive kit.
Also its been mentioned a few times now but if there is too much friction then you might already have harshness present and adding compression is obviously not going to help that.
Just listened to the pt 2 of Darrens podcast and its a great listen!
Yes! This!
The idea of true high and low speed damping in a fork seems a bit of a myth. Its more "bias" isn't it? Like LSC is more biased to adjusting low speed, and HSC is more biased to adjusting high speed, but there is 100% communication, correct? That's how it feels, anyway. They are not truly independent.
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as the velocity increases. So at low speeds the damper is building very little force and is thus not efficient in controlling the chassis dynamics. However, as the velocity increases the force ramps up quickly and can feel harsh on high speed events.
In an mtb fork a digressive curve is better suited to the application. Force is built up early and quickly at low speeds preserving the ride height. Then it increases at a linear rate to avoid the harsh feel.
Since Gwin was mentioned above, in my opinion he's a prime example of stiffer is softer. Just because he's not blowing through travel people assume it's ungodly stiff. A benefit to staying higher in the travel is he could in theory run a slower rebound compared to most others. Slower rebound = more grip
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as...
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as the velocity increases. So at low speeds the damper is building very little force and is thus not efficient in controlling the chassis dynamics. However, as the velocity increases the force ramps up quickly and can feel harsh on high speed events.
In an mtb fork a digressive curve is better suited to the application. Force is built up early and quickly at low speeds preserving the ride height. Then it increases at a linear rate to avoid the harsh feel.
Since Gwin was mentioned above, in my opinion he's a prime example of stiffer is softer. Just because he's not blowing through travel people assume it's ungodly stiff. A benefit to staying higher in the travel is he could in theory run a slower rebound compared to most others. Slower rebound = more grip
Roger. That's what I thought you were really saying. SO a digressive valving configuration would help eh? Sound familiar to any Trek/car racing fans
?
Off topic, but one of the best suspension products I ever ran was an avalanche rear shock on some 4 bar wannabe Intense DH bike back in the early 2000s. I'm sure its just rose colored glasses at this point, but that was the closest I ever felt to having true high and low speed compression set to my liking, and the valving was never harsh.
That bike was responsive to my input, letting me push into jump faces and pump through just about everything but still mow down square edged hits like nothing I have ridden sense. It felt like there were two shocks, one for low speed events (my input) and one for high speed events (rocks, roots, square edged shit). It felt decoupled. It may have used more travel than it should have too often, but man, that thing rocked.
I was faster. More in control. I raced that bike well.
Cool story huh? Lol. Point here is that avalanche shock actually felt like it had some kind of magic going on where it never got harsh, regardless of shaft speed, but was still able to keep me from excessive bottoming. It was awesome.
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as...
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as the velocity increases. So at low speeds the damper is building very little force and is thus not efficient in controlling the chassis dynamics. However, as the velocity increases the force ramps up quickly and can feel harsh on high speed events.
In an mtb fork a digressive curve is better suited to the application. Force is built up early and quickly at low speeds preserving the ride height. Then it increases at a linear rate to avoid the harsh feel.
Since Gwin was mentioned above, in my opinion he's a prime example of stiffer is softer. Just because he's not blowing through travel people assume it's ungodly stiff. A benefit to staying higher in the travel is he could in theory run a slower rebound compared to most others. Slower rebound = more grip
Roger. That's what I thought you were really saying. SO a digressive valving configuration would help eh? Sound familiar to any Trek/car racing fans ;)?
Off...
Roger. That's what I thought you were really saying. SO a digressive valving configuration would help eh? Sound familiar to any Trek/car racing fans
?
Off topic, but one of the best suspension products I ever ran was an avalanche rear shock on some 4 bar wannabe Intense DH bike back in the early 2000s. I'm sure its just rose colored glasses at this point, but that was the closest I ever felt to having true high and low speed compression set to my liking, and the valving was never harsh.
That bike was responsive to my input, letting me push into jump faces and pump through just about everything but still mow down square edged hits like nothing I have ridden sense. It felt like there were two shocks, one for low speed events (my input) and one for high speed events (rocks, roots, square edged shit). It felt decoupled. It may have used more travel than it should have too often, but man, that thing rocked.
I was faster. More in control. I raced that bike well.
Cool story huh? Lol. Point here is that avalanche shock actually felt like it had some kind of magic going on where it never got harsh, regardless of shaft speed, but was still able to keep me from excessive bottoming. It was awesome.
(or maybe my memory just sucks
)
some people bash DVOs valving as they claim are digresive .. some people think everything needs to be progressive regarding suspension...
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as...
I'm not implying damping is position sensitive. I'm referring to the damping curve, force vs. velocity. In a progressive curve the damper builds force exponentially as the velocity increases. So at low speeds the damper is building very little force and is thus not efficient in controlling the chassis dynamics. However, as the velocity increases the force ramps up quickly and can feel harsh on high speed events.
In an mtb fork a digressive curve is better suited to the application. Force is built up early and quickly at low speeds preserving the ride height. Then it increases at a linear rate to avoid the harsh feel.
Since Gwin was mentioned above, in my opinion he's a prime example of stiffer is softer. Just because he's not blowing through travel people assume it's ungodly stiff. A benefit to staying higher in the travel is he could in theory run a slower rebound compared to most others. Slower rebound = more grip
It's not always true that slower rebound equals more traction, is it? Faster rebound can imply the tire more quickly returning to the ground in choppy sections, and should also imply more force directly into the ground after compressions (assuming the rider doesn't get bounced). My understanding is that pros run their rebound extremely fast for these reasons, particularly the first one.
Sounds like your memory of that Avalanche shock is fairly accurate, Mr Brines.
I recently procured a used Nicolai G13 with an Avalanche Woodie (long stroke to bring travel up to 148mm) and revalved DHX, they both work better than any stock shock I've used when I comes to making square edged hits disappear without excessive dive (the "decoupled" feeling you described). Both shocks also have amazing recovery whether it's to the trail or rider input, without feeling too fast or skittish. I have never had a bike with suspension that feels this balanced and well controlled. Part of that is due to the size and wheelbase of the bike (a bike that fits), and having a fork (keep up on those lowers services y'all) that also feels very well sprung and damped (Fox 36 RC2, PUSH ACS COIL). Craig at Avalanche is a freaking suspension wizard and the custom products he offers for different forks and shocks is mind blowing considering he's basically a one man operation, plus his website gives you the feeling of being in the movie Turbo Kid and Kung Fury at the same time. Get him on "The Inside Line"!
Fork Damping VS Spring Rate?: Both the fork and shock springs are on the heavy side of what is recommended for my weight, which I have always preferred for the reasons mentioned by Darren from PUSH on the Podcast and by others here. The damping has softer compression and faster rebound than my previous set-ups, but it's not that far from the recommended "base" settings from AVA and PUSH. I highly suggest doing some bracketing when dialing in suspension using the methods described by Darren on the pod, but get your spring rates right first so you have a solid foundation to begin with.
I used to have a RCT3 Charger damped Pike and I favoured a damping specific setup with a softer spring and more tokens and lots of LSC
I've recently gone to a Charger 2 RC Pike with DebonAir spring and I've found that a spring biased setup is leaps and bounds ahead of a damper biased tune.
I used to run 65psi. 2 tokens and 5 LSC (From fully closed) but now have changed to 90psi, 1 token and no low speed. I'm using the same amount of travel as before but I have more control, slightly better grip but more importantly the mid-stroke is way better than before and I don't feel my fork diving in corners or the steeps. and its made the bike feel more stable so I'm feeling I have more room to let the bike go through sections I would normally be apprehensive in.
I'm a firm believer in a balance between fork and shock. But my one gripe with RS is their rebound tune on their deluxe shocks. I've got 200psi in a Deluxe RT and he rebound has 0 clicks and its not fast enough, which shifts my weight back and gets that wallowy feeling in the rear. Time for a re-tune!
One thing that has come to mind, is why doesn't RockShox/Fox/Etc. have a traveling "pit" that moves around for the summer from key riding place to key riding places to help people with suspension tuning? I would happily pay a fee and get some service done.
Lot of great comments in this thread but one of my biggest takeaways is how easy it is to go down a path that could get you pretty far away from where you want to be.
This has been a great thread.
One thing that has come to mind, is why doesn't RockShox/Fox/Etc. have a traveling "pit" that moves around for the...
This has been a great thread.
One thing that has come to mind, is why doesn't RockShox/Fox/Etc. have a traveling "pit" that moves around for the summer from key riding place to key riding places to help people with suspension tuning? I would happily pay a fee and get some service done.
Lot of great comments in this thread but one of my biggest takeaways is how easy it is to go down a path that could get you pretty far away from where you want to be.
I've been doing something like that locally at our lift-accessed bike park (although a little far from you!) and kinda surprised that it isn't more common? I don't feel like I thought of it but I hardly know of anyone else doing a similar event
Re: suspension speeds - the highest possible speeds happen much earlier in the stroke than most people think - around sag point - so too much HSC can easily effect smaller bumps too
But I have the feeling that I am now even more unsure if my idea for changing the setup is right or wrong. or I am about to adjust the right if I realize that something is wrong. so to speak, as has been explained in the podcast: there is bad good or unchanged, but how do I get too "good"
ive posted my setup a few posts before, if someone is interested. i am already on a stiffer spring with fast rebound. if i close the lsc on the fork i immediately feel the lack of "supple at the top" like you guys described. but on steep stuff the control is lacking.
i will try something out tomorrow and go bracketing a little
this is such a good thread!
But I have the feeling that I am now even more unsure if my idea for changing the setup is...
this is such a good thread!
But I have the feeling that I am now even more unsure if my idea for changing the setup is right or wrong. or I am about to adjust the right if I realize that something is wrong. so to speak, as has been explained in the podcast: there is bad good or unchanged, but how do I get too "good"
ive posted my setup a few posts before, if someone is interested. i am already on a stiffer spring with fast rebound. if i close the lsc on the fork i immediately feel the lack of "supple at the top" like you guys described. but on steep stuff the control is lacking.
i will try something out tomorrow and go bracketing a little
You mentioned in your previous post that your current setup feels great and is well balanced for flat cornering, which is fine, but it's going to mean a bit of a compromise on steep terrain when your weight shift significantly forward. I'll go out on a limb and say it's really not possible to get a setup that is the most optimal on both and you'll have to settle on a compromise. If you follow WC racing, this is the exact dilemma riders have when setting their bikes up for the track in Andorra, where 2/3 of the way down it drops from flat-out fast and relatively flat corners into an elevator shaft.
Sounds like your plan to bracket test different settings is the way to go, but at the risk of complicating your setup more there are a few other factors besides fork spring and damper setting that dictate how your bike handles on steep terrain. One of the biggest influences on your dynamic ride height is going to be your body position. Because we weigh so much more than sprung mass of the bike (about 6 times as much in your case) simple changes in position have significant effect on suspension.
Aside from spring/damper settings at the fork, if the front end feels too low on steeper terrain the first thing I'd consider is raising the bars a bit. While I have a 'standard' bar height I stick to most of the time, I'll regularly raise them 2.5 to 5 mm if needed. Higher bars might mean you need to consciously weight the front end more on flatter terrain, but again all setup involves compromise, and if you know you have to do it eventually it becomes habit.
Steep terrain also lengthens your effective reach, and that feeling of your hands getting farther way from you can feel like the front end is diving too much. Again this can be addressed with bar height or stem length. And while I touched on it earlier it's worth repeating that raising your bars via stem spacers slightly decreases your reach due to the head tube angle. If you feel like it's getting too short, higher rise bars raise your hands up without shortening the reach.
As if that's not too much to consider, you can also counter the front weight bias that occurs on steep terrain by making changes to the rear shock to help the back end 'sit down' a bit. Lowering pressure, increasing rebound damping, or decreasing compression damping on the rear are all ways to shift your weight towards the back wheel a bit.
It's not uncommon for riders to set their bikes up with the rear ever so slightly softer than the front to create more balance when descending. The trade off, of course, is that you'll have to intentionally shift your weight to the front on flatter terrain and especially in flat corners.
If you haven't watched the Dialed series Fox is producing this year I'd recommend checking it out to see the kinds of changes racers are making to address these same challenges, and it does a pretty good job explain both why certain adjustments are made and others are not.
If there is one thing I absolutely hate about modern suspension, its how easy it is to contaminate the lowers. Frequent service, though easy, is annoying, and just as important as lubing your chain or similar. Why is it not as easy as lubing your chain?
Part of the problem is the inherent design of "right side up" forks. I'd be very willing to go USD and take 1.5 pounds. Yeah they are 'flexy'. I think this is blown way out of proportion.
Alternatively, Fox has a patent on a really cool oil re-circulation system that will help keep oil around the seal, and going through all the bushings.
Regardless, I could see adding more damping if the bushing/stanction interface was likely to stay smooth sliding, and we eliminated how much bushing bind we get when twisting the fork.
I've always thought of compression damping as slowing down a fork's movement to it's spring balance point. And I want the fork to move as fast as possible in response to fast, square, edges. I use my arms a lot for travel as well and that is where I exercise control. So I am more of a spring/open damper rider.
I also wanted to point out, we are on mountain bikes where the body can handle so much more of the impact compared to say, a dirt bike or (obviously) a RZR, UTV, baja truck etc.
That's a lot of the equation that has to be tricky as hell to balance out. I will literally put my face into my handlebar on my dirt bike if I over jump something without adequate damping. Mountain bike, usually its on me to BMX through the event (BMX guys have zero travel and make us look like wusses 99% of the time when it comes to "big hits")
Like I mentioned earlier, most people don't have what I'd call "big hit" type of terrain over and over, its more roots, square edged rocks, etc with maybe one huck to flat or questionable double on the entire track. To tune for this one huck seems like putting 35s on your Chevy just to drive down the highway 99.9999999% of the time.
True or not, that Grip 1 is no slouch of a product.
Although I am running less Air then recommended, a volume spacer, and faster rebound on a 160 then my weight recommends. I'm 185 with 72 PSI, 7 LSR, 4 HSR, 15 HSC and 11 LSC as base settings and then adjust compression as needed.
FWIW, the Fox told me those settings are ball park and not to pay much attention to them. Setting sag, rebound based on a quick hit and release to see if the tire skips, and then rolling bunny hop to check volume (80% of travel) is what should be your starting part. Then adjust from there based on ride experience. I actually think Jordie does this in one of the dialed episodes.
I'm 155-160lbs with 61psi, one token, HSC 2 clicks from fully open, LSC 5 clicks from fully open, and rebound as fast as I can get it based on the tire-staying-on-the-ground test (5 clicks from fully open).
When I first got my bike, I set the fork up close to Fox's recommendations, went to a gnarly enduro race (unfortunately the bike was backordered, and I didn't get it until the weekend before the race), was beaten to death because of the compression settings, drove the whole way home pissed, rented a Shockwiz, was implicitly taught how to set-up suspension with a mini computer and an app, and have been pretty stoked on my bike ever since.
Interesting to note that I raced two races in a four week period without and then with proper set-up, and, compared to the fastest pro who attended both races, I went from 14% back (10% back when removing a stage where I had a big crash) to 2.3% back. Likely had a lot to do with getting comfy on the bike in general, but I tend to think suspension set-up played at least as big of a role.
The experince of the linear setup with a coil in the front, makes me wonder about a coil setup in the back. I dont have to most progressive frame(cube stereo 150) but from what i feel in the front, i really want to Try. The support from the beging stroke is tempting..
Spring rate is the most important thing to get set up, it's what supports your weight and pushes the wheels back to the ground so has the biggest effect on how the bike responds to bumps. The damper dissipates the "left over" energy to help the spring use only the travel it needs to, putting in a simple way.
On the topic of damping though, it is wrong to think that adding compression damping automatically means you a "restricting" your suspension or adding harshness, it is there to absorb energy so everyone needs a certain amount of that, which varies depending on the speed and aggression you ride at. Don't be scared of it! I'm not saying everyone should be running loads of it, but every brand has wildly different ranges of adjustment so running your adjusters open could mean you are so far off the end of having barely any damping that it becomes harsh again.
Push's Mr. Murphy too touched on this. Going firmer to make it feel softer...
This was the other part of me putting up this thread, as I understand all this in theory, it just doesn't seem to pan out in practice. Likely, because I suck.
Very good topic and good discussion. This is something I've done a LOT of testing on.
I've built myself a franken-36, Just stuff I had laying around combined with a purchase of a Grip2 damper, it's impressed me but I think there is a bit more work that can be done.
36 Rhythm CSU and Stantions. (44 offset)
36 Factory Lowers (29 inch)
Grip2 Damper
Vorsprung smashpot at 170mm with 55lb spring, hydraulic bottom out
SKF seals
I tossed and turned between a 50 and 55lb spring with damping added to suit the lower spring rate. In the end I preferred the 55 with basically no damping at all and a pretty quick rebound.
Interestingly, the grip2 isn't night and day better than the FIT-GRIP. I'd probably save my money if I was to do it all again. Very good and underrated damper.
Lee had some pretty good bullet points and I'll echo some things already mentioned above.
The spring should set your ride height (i.e. sag) and control your bottom out. You shouldn't really ask it to do much more than that. It gets complicated because of the ratio of sprung mass to friction in mtb forks. The added stiction can throw off setting your ride height, but getting the spring dialed is the first step to a proper set-up.
On to the damping... First that same friction adds damping and it can be a significant percentage compared to the actual damper. Plus, this force can be position sensitive due to chassis flex, internal alignment, etc, etc. Bottomline, you might have the compression “wide open” because of the added friction in the system. (Take some time in a parking lot to adjust the tightness of your thru axle, you might be surprised how much friction it can add.)
The other issue on most mtb forks is the shimmed HSC circuit is progressive in nature. The progressive damping is decent for big hits but really lacks in chassis dynamics (i.e. staying higher in the travel). I haven’t listened to the pod cast yet but it was mentioned above, if you’re staying higher in the travel it can actually feel softer since you’re at a lower spring rate/ less progressive area.
Overall, fork set-up preference varies by rider more so than shocks and combine that with manufacturing tolerance is hard to get a small window that works for everyone. -Matt
Also its been mentioned a few times now but if there is too much friction then you might already have harshness present and adding compression is obviously not going to help that.
Just listened to the pt 2 of Darrens podcast and its a great listen!
i have a trek slash with a 160mm grip 2 fork
my actual setup: 1 spacer 82 psi, 8 lsc 14 hsc and 4 hsr 5/6 lsr. at the moment 5 lsr caused by higher temperatures.
x2 on the back with 220 psi, 14 hsr 16 lsr 15 lsc and 14 hsc, full on spacer. the pressure is higher than normal caused by the longer shock stroke 60mm (standard is 57,5mm)
measured sag (standing, not sitting) the front is nearly 16% and the back 28%. full travel front only when i nearly die on a huck to flat, full travel back more often. tyre pressure 1.65 front assegai DH and 1.9 back aggressor DD.
my bodyweight is 82kg naked
i would describe it as an active setup, good grip and small bump on flatter trails. really nice balance for flat cornering.
if i really push into big compressions i feel that it lacks compression - bouncing through travel. but again a really good setup for riding playful.
on steeper trails like 15-20% drop, i really feel that the front end is to low (when breaking) to ride aggressive. i like it to break hard on my breaking points and not be dragging to much. in this moments i feel that i need more support. i fiddle around with compression on the front but could not find a sweet spot. if i close for 1-2 clicks on lsc/hsc i am immediately loosing grip cause the tyre tracks the ground way less when it gets flat again....?
dont know if i can get a better overall feel with more/less psi, more/less rebound oder compression. also the back of the slash is packing down if i have to break hard. rebound is already fast. maybe i have try to close compression to ride higher in the travel..
I'm not sure I agree with the bit about spring only controlling ride height and bottom out, but this is exactly what I wanted to talk about.
Considering the nature of a modern air spring, and how adjustable it is with respect to volume, pressure and to some extent negative spring volume, it seems we can tune this, too, add support (or not) where we want it. Its not something we can fully manipulate, but we can do so to a much larger degree than we could a decade prior.
On that note, I'm shocked (no pun intended) we haven't seen progressive coils in a fork. I know, space limitations, but yeah, a semi-related side point.
I touched on the bit about friction's impact on the overall fork's performance earlier, and I really believe this is a huge variable on all of this. I pointed this out way back when the Pike was released, but bushing bind is one of the biggest issues I see with current fork design and literally nobody is addressing it. The fork has substantially more friction going through its stroke when a twisting force is applied than when cycling in a centered fashion. Obviously, heavier riders are more prone to experiencing this than lighter riders. Another reason an USD fork that allows a little flex to keep things cycling straight may actually be a good thing...
When you say "progressive nature" with respect to HSC, are you suggesting it is position sensitive? Not really following there. I always thought if you were too light on your LSC, you'd run into your HSC too quickly, making it feel firmer, though it has nothing to do with where you are in the travel...
The idea of true high and low speed damping in a fork seems a bit of a myth. Its more "bias" isn't it? Like LSC is more biased to adjusting low speed, and HSC is more biased to adjusting high speed, but there is 100% communication, correct? That's how it feels, anyway. They are not truly independent.
Good info - thx for the post!~
In an mtb fork a digressive curve is better suited to the application. Force is built up early and quickly at low speeds preserving the ride height. Then it increases at a linear rate to avoid the harsh feel.
Since Gwin was mentioned above, in my opinion he's a prime example of stiffer is softer. Just because he's not blowing through travel people assume it's ungodly stiff. A benefit to staying higher in the travel is he could in theory run a slower rebound compared to most others. Slower rebound = more grip
Off topic, but one of the best suspension products I ever ran was an avalanche rear shock on some 4 bar wannabe Intense DH bike back in the early 2000s. I'm sure its just rose colored glasses at this point, but that was the closest I ever felt to having true high and low speed compression set to my liking, and the valving was never harsh.
That bike was responsive to my input, letting me push into jump faces and pump through just about everything but still mow down square edged hits like nothing I have ridden sense. It felt like there were two shocks, one for low speed events (my input) and one for high speed events (rocks, roots, square edged shit). It felt decoupled. It may have used more travel than it should have too often, but man, that thing rocked.
I was faster. More in control. I raced that bike well.
Cool story huh? Lol. Point here is that avalanche shock actually felt like it had some kind of magic going on where it never got harsh, regardless of shaft speed, but was still able to keep me from excessive bottoming. It was awesome.
(or maybe my memory just sucks
I recently procured a used Nicolai G13 with an Avalanche Woodie (long stroke to bring travel up to 148mm) and revalved DHX, they both work better than any stock shock I've used when I comes to making square edged hits disappear without excessive dive (the "decoupled" feeling you described). Both shocks also have amazing recovery whether it's to the trail or rider input, without feeling too fast or skittish. I have never had a bike with suspension that feels this balanced and well controlled. Part of that is due to the size and wheelbase of the bike (a bike that fits), and having a fork (keep up on those lowers services y'all) that also feels very well sprung and damped (Fox 36 RC2, PUSH ACS COIL). Craig at Avalanche is a freaking suspension wizard and the custom products he offers for different forks and shocks is mind blowing considering he's basically a one man operation, plus his website gives you the feeling of being in the movie Turbo Kid and Kung Fury at the same time. Get him on "The Inside Line"!
Fork Damping VS Spring Rate?: Both the fork and shock springs are on the heavy side of what is recommended for my weight, which I have always preferred for the reasons mentioned by Darren from PUSH on the Podcast and by others here. The damping has softer compression and faster rebound than my previous set-ups, but it's not that far from the recommended "base" settings from AVA and PUSH. I highly suggest doing some bracketing when dialing in suspension using the methods described by Darren on the pod, but get your spring rates right first so you have a solid foundation to begin with.
My opinion from the past couple years on RS,
I used to have a RCT3 Charger damped Pike and I favoured a damping specific setup with a softer spring and more tokens and lots of LSC
I've recently gone to a Charger 2 RC Pike with DebonAir spring and I've found that a spring biased setup is leaps and bounds ahead of a damper biased tune.
I used to run 65psi. 2 tokens and 5 LSC (From fully closed) but now have changed to 90psi, 1 token and no low speed. I'm using the same amount of travel as before but I have more control, slightly better grip but more importantly the mid-stroke is way better than before and I don't feel my fork diving in corners or the steeps. and its made the bike feel more stable so I'm feeling I have more room to let the bike go through sections I would normally be apprehensive in.
I'm a firm believer in a balance between fork and shock. But my one gripe with RS is their rebound tune on their deluxe shocks. I've got 200psi in a Deluxe RT and he rebound has 0 clicks and its not fast enough, which shifts my weight back and gets that wallowy feeling in the rear. Time for a re-tune!
One thing that has come to mind, is why doesn't RockShox/Fox/Etc. have a traveling "pit" that moves around for the summer from key riding place to key riding places to help people with suspension tuning? I would happily pay a fee and get some service done.
Lot of great comments in this thread but one of my biggest takeaways is how easy it is to go down a path that could get you pretty far away from where you want to be.
Re: suspension speeds - the highest possible speeds happen much earlier in the stroke than most people think - around sag point - so too much HSC can easily effect smaller bumps too
But I have the feeling that I am now even more unsure if my idea for changing the setup is right or wrong. or I am about to adjust the right if I realize that something is wrong. so to speak, as has been explained in the podcast: there is bad good or unchanged, but how do I get too "good"
ive posted my setup a few posts before, if someone is interested. i am already on a stiffer spring with fast rebound. if i close the lsc on the fork i immediately feel the lack of "supple at the top" like you guys described. but on steep stuff the control is lacking.
i will try something out tomorrow and go bracketing a little
Sounds like your plan to bracket test different settings is the way to go, but at the risk of complicating your setup more there are a few other factors besides fork spring and damper setting that dictate how your bike handles on steep terrain. One of the biggest influences on your dynamic ride height is going to be your body position. Because we weigh so much more than sprung mass of the bike (about 6 times as much in your case) simple changes in position have significant effect on suspension.
Aside from spring/damper settings at the fork, if the front end feels too low on steeper terrain the first thing I'd consider is raising the bars a bit. While I have a 'standard' bar height I stick to most of the time, I'll regularly raise them 2.5 to 5 mm if needed. Higher bars might mean you need to consciously weight the front end more on flatter terrain, but again all setup involves compromise, and if you know you have to do it eventually it becomes habit.
Steep terrain also lengthens your effective reach, and that feeling of your hands getting farther way from you can feel like the front end is diving too much. Again this can be addressed with bar height or stem length. And while I touched on it earlier it's worth repeating that raising your bars via stem spacers slightly decreases your reach due to the head tube angle. If you feel like it's getting too short, higher rise bars raise your hands up without shortening the reach.
As if that's not too much to consider, you can also counter the front weight bias that occurs on steep terrain by making changes to the rear shock to help the back end 'sit down' a bit. Lowering pressure, increasing rebound damping, or decreasing compression damping on the rear are all ways to shift your weight towards the back wheel a bit.
It's not uncommon for riders to set their bikes up with the rear ever so slightly softer than the front to create more balance when descending. The trade off, of course, is that you'll have to intentionally shift your weight to the front on flatter terrain and especially in flat corners.
If you haven't watched the Dialed series Fox is producing this year I'd recommend checking it out to see the kinds of changes racers are making to address these same challenges, and it does a pretty good job explain both why certain adjustments are made and others are not.
For your current dilemma the Andorra round might be a good place to start: https://www.youtube.com/watch?v=HHXZk8ke7sM
For initial setup: https://www.youtube.com/watch?v=GPQnjSe6rdw&t=7s
Good luck!
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