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Yeah that does seem to be whats going on, and they have provided some decent graphs which is much better than a lot of companies. I think my initial reaction has been a bit prickly since Vorsprung made a coil-like air spring a while ago now and this actually has enough unique features that it didn't need to make that claim.
I have actually wanted air springs to feature more adjustability - major fork brands have been resistant to go fully towards a secus-like air spring curve so a design that has more fine tuning, especially in the first third of the travel could be useful in dialling in a particular feel. The current lyrik is one that just came to mind where Rockshox locked in a much more "trail" feel compared to the Zeb, but riders who want that feel of the Zeb in a shorter/lighter chassis have to compromise on some sensitivity. I think the 36 is much closer to a 38 than a lyrik is to the Zeb for comparison.
I know my last few opinions on these air springs have been fairly negative, it just seems like companies are looking for complex solutions to solve problems when things like optimised damper tunes haven't been used to their full potential (and are plenty well understood already)
What can I spect from a d1 lyrik "ultimate" (charger 3.1) (I found some very good deals around latelly, so I end up buying a Lyrik base and ultimate internals for very cheap)
For reference, I came from a '19 fox 36 performance that I really hate (it become only rideable to me after a luftkappe and some mods to the negative chamber + a different, harsh but at least supportive, comp shim stack) In stock form the fork always worked too low in its travel, and rebounded too abruptly, forcing me to run 2-3 lsr from closed, wich I am sure worsened my problems with this fork. After all the mods at least I was abble to run Lsr in the middle. I'm about 200lbs, running 95psi or so.
I'm almost sure I will end up kinda dissapointed with my new fork too ,but I just want to try a completly different stock setup from what I know, and build from there if needed
Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1 Select+ (Charger 3.0 / 27.5 / 160mm)? Friend in question just got his 9 year old ripper a size XS Bronson 4.1 that came with that fork. The kid is only like 80 lbs fully geared up with full body armor and DH helmet. He races BMX and will be riding the bike at Northstar every weekend next summer. In stock config he couldn't use more than like 90mm travel with no tokens and rebound wide open. Friend added a Noken to it, which let him use more travel even with a few psi more, but then the kid kept wanting to add pressure to make it poppier since the rebound is already wide open, and he's back to only using like half the travel and gets worn out after 3 laps. We're thinking we need the damper replaced or revalved with a custom extra light tune. I can hone bushings for him and could install a 3.1 conversion kit, but don't know anything about creating a custom shim stack (the only rebound tunes RS lists in the manual for that are "regular" and "heavy").
Open to suggestions. We're in California so the closer the better. He'd like to not have to send in the whole fork somewhere because of shipping costs & taking the bike out of commission. He talked to Avalanche and Craig didn't want to do anything for only the fork, only a package deal with a shock. The bottom end of the lightest MRP Lift damper tune is about 20 lbs heavier than the kid.
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:
The standard and heavy tune is for LSC, rebound also comes in a light tune with the 3.1 upgrade.
The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what is suggested in the stack for a kid that light
When the fork dives under brakes the spring gets stiffer and you are adding harshness that way - if its dialled in well the forces should balance out enough to retain compliance rather than "resisting" the bumps. It's like the Trust forks - they were very controlled under braking and turning because they didn't load up the wheel too much or change geometry in turns which felt a little weird but actually pretty confidence inspiring. They did suffer with comfort/sensitivity but it was for different reasons and not strictly under braking
Thanks, looking at the manual now, I must have remembered the Comp tune. So you're suggesting taking the "Light" tune stack of 14(0.15)x3 - 7(0.3)x4 - 14(0.1)x1 (all 5mm ID) and dropping that to 14(0.15)x3 - 7(0.3)x4? Eliminating the 14mm OD 0.1mm thick single shim?
Don't I need to maintain the same overall stack height (1.75mm)? If I'm doing my math right, what I could do is eliminate 2 of the 14mm 0.15 thick shims and add 1 7mm 0.3 thick spacer.
Assuming what I'm thinking about the stack height needing to remain the same, I don't see any way to reduce the Comp "Standard" tune without sourcing custom spacers.
The 14x0.1 is the check shim so leave that in - I would instead take the original medium tune (3 x 14mm OD shims and 2x 12mm x 0.15mm shims) and leave 1 x 14 x 0.15 and 1 x 12 x 0.15. Stack height I don't think is mega critical but it is good practice so what you can do is place the spares between spacer shims where they will do nothing ie-
Piston
14 x 0.15
12 x 0.15
7 x 0.3 - spacer
14 x 0.15
14 x 0.15
12 x 0.15
7 x 0.3 -spacer
7 x 0.3 -spacer
14 x 0.1
the 0.3 is thick enough that the shims will never flex far enough to touch the spares. On the compression piston, you can move a spacer shim between the face shims somewhere to reduce the preload - between the first and second reduces the compression damping to hardly anything, or moving it up in the stack retains a little bit of damping if you need it at some point. You need 1 shim in contact with the piston to maintain a seal. Or you can remove face shims and put them behind the spacers again, but I find reducing the preload is pretty effective for very light riders
Got it, seems pretty straightforward. Looks like a fun weekend project. I'll probably split the difference on the compression side, putting the spacer in between #2 & #3, seeing as how I'm of the opinion some damping is better than none. Thank you so much for your help.
What is old is new again?
History repeats itself?
Those who forget the past…?
More than 40 years ago you could buy any number of sportbikes that featured anti-dive systems on the front end. They had been used on factory roadracers, then trickled down. The systems disappeared from the race bikes, then from the production bikes shortly thereafter. Maybe an eight or nine year span altogether. In that time they learned that effective damping was better than a non-moving suspension. That and the fact that the steepened head angle helped with the turn-in once they started using Deltabox(beam type) frames that could stand the forces that slicks put into the frames.
I was going to post a picture of a bike from the 50's in this book I have.......but realised this device only moves the mounting of the brake and the axle is still following the regular fork tubes? So I guess under brakes the torque is tying to extend the fork which is a little different to typical anti-dive geometry
i had an rz500 (2 stroke!) that had a rudimentary anti-dive system that was comprised of a T off the front brake line that actuated a fork compression circuit. unsurprisingly, it was not great in practice.
Yep, the bikes I had with the feature were RZ500, GPz550, V45 Interceptor, and a CB1100F. Skipped street bikes for a while and just like that my 1989 FZR600 had no anti-dive.
A new and improved version of Intend's Hover shock just dropped - video and full press release below:
OK nerds, have a live one for you. Am I nuts thinking it'd be pretty freaking sweet for sus co's to specify what their stock air spring volumes are for forks and dampers? I posit after a bit of a lengthy chat with a pal about why the X2 on his V2 Ripmo isn't the greatest choice for the platform and the bike would be better suited with a smaller spring volume, citing the playfulness of my V3 Rip. Bear in mind he's had the bike since new and never got used to the plow feel, preferring a spunkier ride. I thought it'd be sweet if we had access to that info as well as the piston diameters for those of us who like to do the math so we can better understand and show the rate change effects.
So, silly or no?
I'd say no.
Those ratios can be calculated easily enough by a shockwiz, or anyone with a shock pump and a couple minutes.
A "spunkier" ride developed through a higher ratio air spring is typically more detrimental to descending performance as a whole. It simply makes the damping more inconsistent.
Can't say as I've ever heard of a ripmo described as a plow, the dw link is typically the opposite of that on any kind of a fast descent with square edged hits. I had a coil on mine, and it still sucked.
was silent launched earlier this month 😁
I've had it for a few solid rides now, spectacular shock!!
Yeah it would be pretty sweet if that kind of data was published, along with a few other specs. Would be useful for picking air shocks and deciding when a Float X or X2 is the better choice. And when Rockshox has 3 different types of air can I still can't keep up with exactly which is supposed to do what. You could see roughly what pressure in an X2 gives equivalent sag in a Float X if you swap it out.
I think you might be right the Float X is probably better for a Ripmo V2 though
In my ignorance I had assumed, apropos of nothing, that suspension tuners would have developed an heuristic for that by now, e.g. "above a certain leverage ratio (or other characteristic) = Float X2, below it = Float X", or something along those lines, although I'm sure it isn't that simple.
How difficult is it to measure the chamber volumes when it's already open for service? I imagine filling each chamber with an appropriate incompressible fluid, but I don't know enough about the insides of an air shock to know whether an "appropriate fluid" exists or if they'd tolerate that kind of thing in general.
What are your thoughts about the Hover Monocoque?
I kinda agree that the Secus already addressed these issues. There is no replacement for displacement, expanding lower and negative volumes in an external device was pretty innovative engineering.
Yeah theres definitely some rough guidelines we pick up, but measuring air springs accurately is tricky so a lot of it comes down to rider feedback and trends as much as measuremements. And part of that for me is not being able to 100% confidently measure the full stroke of an air shock accurately across a range of pressures without a way to validate those tests. Each stroke shock and even trunnion and standard eyelets have different volumes so its a big task to collect data on all of them.
Ive tried measuring a few different ways, all are pretty fiddly - you can fill it with oil or degreaser and weigh the shock before & after bit you still need to work our how much was in each chanber. The inside of the eyelets are awkward shapes so cant be directly measured either. It can be done, its just not always worth the amount of time it would take to work it out. Ive been playing with 3d scanning/photogrammetry and there is potential there for measuring things quite accurately though, so ill look at giving that a try for shock volume soon
Not too many sorry - we dont really get any intend product down here so have no direct experience with it apart from bouncing on 1 or 2 of their forks and shocks on tourists bikes. They did feel quite impressively smooth for air suspension though! Ive always been a coil fan so havent looked too closely at them otherwise, they seem really nice its just not my cup of tea
3D scanning might work (likely expensive), photogrammetry probably won't work as you need to look very deep into the air chamber to see the shape of it, it's shiny and usually black, so I doubt you'll get any meaningful results from photogrammetry.
3D scanning is much more likely to work as it also projects (in IR) patterns onto the surface plus looks at the object using two cameras and the part has to be covered with something like TiO2 to be nice and matte to prevent reflections. But you're again back to square zero where you have to measure each and every shock option, it will more or less be a throw-away shock as it will be hard to properly clean the TiO2 from all the surfaces, etc.
It's a very expensive endeavour for something that a) is likely something the manufacturers already have and need to develop the platform correctly and b) would be very easy for the manufacturers to share and c) would not give anything away design wise as those who could realistically benefit from it, easily buy competitor products and analyse them (it's VERY hard to imagine the like of Fox, Rock Shox, Suntour and Manitou don't have 3D scnaning, dynos and other equipment in house and can't afford 20 to 30k to investigate competitor products once those come out).cha
FWIW, if data was shared, starting volumes of both positive and negative chambers, piston surface area and equalisation stroke point is what would be needed to fully model the shock for an enthusiast (spring stiffness wise).
Possible (but not at all serious) solution: DIY CT scanner
Perhaps plow was the wrong term to use. It is decidedly less poppy in ride feel than the V3, much more eager to keep the back end on the ground.
I’ve always been suspicious that changing shock stroke changed the air volume on my X2.
I extended the stroke from 62.5 to 65 and it felt softer even at the same sag (by distance in mm, not by %). I put a volume spacer in and it felt similar to the prior stroke.
Absolutely, if that's what you are after. Even with a coil though, I thought the v2 was plenty "poppy". It's the nature of the dw link and relatively short chainstay. My terrain here in western canada tends to be higher speed stuff though, so I am definitely bent that way in terms of bike setup.
I'd agree that it's going down the rabbit hole to actually measure volumes, shaft displacement, piston area, transfer port locations and attempt to extrapolate a curve.
The layman can suss out 90% of what they need by simply calculating compression ratio. But it's all arbitrary in most cases anyways when we are talking about applying this to a trail bike like a ripmo. An x2 is easy enough to tune, throw some volume spacers in it. Add some lsc, you'll be popping around like Jeff KW in no time.
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