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I haven’t taken it apart, so no, I can’t guarantee it, but that’s Push damping. They do poppet style valves in the 11.6, HC97, 9.1, etc. The rebound is standard shims (like they do in the 11.6)
Main piston is shimmed for compression and rebound in all Push shocks, the adjuster uses a coil spring backed valve with no shims and adjustable preload for HSC. The standard bomber CR also uses a spring backed valve but its a very stiff belleville washer instead of a coil, and no shims either. At a distance they have similar basic architecture but the actual execution is very different
Some kind of preloaded valve usually works well at the base valve - its rare to see a regular unpreloaded shimstack in the reservoir. It helps maintain back pressure on the main piston until the shims open, otherwise you need very minimal bleed or very high gas pressure to prevent cavitation. It gives decent adjustment range and allows the main piston to be used for custom tuning. Some will be a shim stack + spring while others are just a spring, but the piston design can have just as much influence on the actual damping curve so shimmed valves can still be very digressive and spring loaded ones progressive
The ELEVENSIX, VT/X, and SV EIGHT all used shim-based compression and rebound stacks. All three use the same architecture for the base valve, which is shimless and manages the external adjustment range of the compression circuit. External rebound is controlling the low-speed free bleed. Damper tuning is all done via traditional shim stacks, so the tuning variables are almost limitless. There's obviously a lot more to it, but that's the general makeup of the three rear shocks.
Darren
The SV EIGHT is a fully shimmed damper. The newer Transition models have high-rising rate designs....maybe we just needed to get you on a firmer tune.
Darren
Thanks @PUSH Industries for the response - I really appreciate the detailed information on the function of the dampers. As I get older and willing to do more work on my own suspension, I’ve really enjoyed learning about oil flow, shims and the workings of different dampers.
I’ve REALLY enjoyed Fluid Focus’ openness - when I wanted to go up a tune on my own, they provided me a spreadsheet with all of the possible tunes, and were swift in getting me the shims I needed. Shockcraft’s system is also cool, but Dougal isn’t as open with his exact shims stacks, only providing a printout and no actual measurements of shims.
Still waiting after a big rain to get out on my new Telum, but can’t wait to contrast it with the other dampers we’ve discussed here!
I follow a lot of these threads, almost no company responds directly with info. Except PUSH. Very much appreciated
Yeah, I’ve been impressed not just that Push do respond but that they keep doing it so consistently when often they give detailed info to people who don’t understand it and it all goes south.
Nice work Push.
Went ahead and tried out the FF CR build with springdex thanks to SWS's recco. I got to say I am super impressed. It has better sensitivity off top even allowing me to go up in spring rate a bit. Its rebound is way better controlled and having a mid valve between the high and low speed comp really keeps the whole thing very composed and calm feeling everywhere.
I have been curious about trying a PUSH SV8 to see how it compares to the other coil options.
@PUSH Industries , seeing as the SV8 is a shimless base valve design, how many different base valve tunes do you offer? Is it possible to order multiple variations to test when purchasing the shock?
Initial disclaimer....My opinion is that a shock dyno is a necessary tool when tuning dampers. Adding shims, or increasing shim thickness, doesn't always make the damper firmer. Likewise, removing shims or reducing their thickness doesn't always make the damper softer. More specifically, base valve tuning is far more sensitive and requires extensive knowledge and equipment to tune properly.
In a monotube damper with external compression adjustment, the base valve serves two roles.
1. It's the foundation for pressure balance inside the damper, which is critical for proper overall function and maximizing performance.
2. It sets the adjustment range of the external adjuster(s).
I mention all of this simply because our rear shocks use a single base valve tune set to work with the range of valving codes we offer for the main damper piston. This ensures a very broad range of tuning options without the risk of damper imbalance.
Darren
Interesting, thank you for the reply.
Not that they are the paradigm of suspension companies by any means, but a quick glance shows that Fox offers 5-6 different stock base valve tunes (fully shimmed) for the DHX.
Is a single base valve tune really the most effective and will provide the largest tuning range for a given shock, or is it more a means to cut product SKUs and cost? It looks like the SV8 only has two stock main piston tunes, A or B. Surely the range of tuning options could be broader with numerous main piston and base valve options? Perhaps this is why the SV8 feedback I have heard is very polar, it seems to be "works amazing" or "is harsh and not compliant". Maybe peak performance is limited to certain frames and riders based on the tunes available.
This also leads back to the potential limiting factors of a "shimless" or poppet valve style damping design. A fully shimmed damping circuit is easier to alter (specifically for the end user) and has a much wider range of tuning characteristics available than the typical shimless spring backed plate system.
I think of poppet valve damping systems like a McDonlads cheeseburger. They are the same for everyone, and quality is very consistent. But if you prefer a burger cooked rare, want a veggie patty, or want pepper jack and guacamole on it you are SOL.
FOX is very good at what they do -Large scale OEM supply. Their strategy is obviously very different than ours.
As for the SV8, your feedback experience is very different from what we’re experiencing. I guess customers may be unhappy and just not reaching out to us for assistance. If it were me, I certainly would be reaching out for tuning help, and I would hope that our paying customers would do the same.
It’s important to point out that shimmed and shimless base valves have similar limitations, the same available damping range, and require the same effort when altering them.
I also think it’s important to point out that in a monotube damper, the primary damping comes from the main piston. The base valve, as I mentioned above, is for setting the external damping adjustment range given to the rider, along with its fundamental role of pressure balancing the damper.
Base valve tuning provides micro-tuning, whereas the main piston provides tuning across the entire range of velocities and movements. So, your analogy of the cheeseburger is much easier to achieve with main piston valving and generally doesn’t come at the risk of base valve damping imbalance....the most widely recognized being cavitation.
Darren
Have you tested the different base valve tunes in the Float X/DHX? Most of them have excessive free bleed (the adjuster already has plenty of range) so I've normally only used their standard medium (no bleed) configuration in the past. It makes the changes on the main piston more noticeable while retaining plenty of external adjustment. I've found tuning the base valve means it either ends up too soft so you have no adjustment range and need high pressure to prevent cavitation, or its too stiff and you can't make the main piston tune soft enough. There is normally a middle ground which covers a wide enough range without needing multiple tunes. The new DHX2 shocks I've tested so far also have next to no adjustment range despite multiple base valve tunes.
The Cane Creek Double Barrell/Ohlins TTX25 had different valving options but they also changed the low speed circuit to match the high speed valves since just changing the high speed wasn't enough to get the range needed.
Vorsprung only had 1 base valve configuration for the Super Deluxe Tractive system too
Speaking as a Push Dealer I have found they listen to feedback and will add tune options if the current ones don't offer the range needed. The SV8 does already have options for different tunes if the customer needs it
I find myself locking out my pedal bike ('23 Smuggler) air shock often to improve pedaling performance. As my terrain is undulating, this is a PITA.
There are a couple of Fox Live Valve DHX (Coil) Neo Live Valve shocks out there that I can buy (the entire kit) for about the cost of a new mid-level coil shock.
Any opinions on this product's performance (ignoring the price)? I honestly hate batteries on my pedal bike but less than I hate trying to reach down and find that shock switch scores of times per ride.
Today, I was able to ride my Bomber Cr with the Fluid Focus Kit for the first time. Is it normal for the rebound to be quite loud? It makes hissing and slight whistling noises...
Yes that's normal
Sorry if this sounds reductive, but what basics have been done? What shock is on the bike currently, sag level, low speed compression adjustments? There is a bunch of great shocks out there, sounds weird that you need to go electronic to make a Smuggler with a decent platform pedal reasonably.
That's fair. That stuff is fairly dialed but things can always be made better. On this bike, I'm also willing to sacrifice suspension feel for a better pedal platform.
As such, I added 3psi (which should have me closer to 27% sag) and clicked in LSC 2 clicks on my Cane Creek Inline Air shock, and it definitely improved pedaling performance.
With the ease of access to the shim stack, there has been a lot of experimenting with the DHX/Float X base valve tune. I have tested changes to the preload as well as overall stack stiffness (never with a slotted face shim). There were improvements over the stock configuration in some cases, with corresponding changes to the main piston tune as well.
For the manufacturer, having a middle ground base valve tune that provides a wide clicker range is good and will suit the largest number of people out of the box. However, if you end up at either end of that range, adjustability and adaptability is sacrificed (and potentially performance). If the tuning goal is to be "optimal" right in the middle of the adjustment range, that can involve changing the base valve tune.
The performance of the PUSH SV8 is a moot point unit one is tested, maybe it's perfect! I simply find a shim stack base valve configuration superior to a spring loaded valve system for it's potential to be tuned and adjusted.
I'm confused by this comment: "I simply find a shim stack base valve configuration superior to a spring loaded valve system for it's potential to be tuned and adjusted."
My confusion just comes from the fact that spring loaded base valve systems can also be tuned and adjusted. As an example, our ELEVENSIX shock uses a different tune in each of the base valves. The tune for Valve 1, which is the Silver high speed dial, is different from the base valve tune in Valve 2, which is designated by the Black high speed dial. So, if you set both sets of clickers to the same position, the shock will still ride differently when you toggle between the valves. It generally wouldn't be recommended, but there's nothing preventing someone from putting the stiffer ELEVENSIX base valve tune in an SV8.
I've pondered this before. Seems to indicate that an air shock would actually provide more suspension travel then it's coil counterpart, especially when I compress the sag ring off.
I have a question. I would like to replace the spring on my Bomber CR. I currently ride a 400. I would like a 425. Which models are compatible? Super Alloy has already been mentioned. Is there also a spring in titanium or titanium look?
Ah I sure do miss all the ti coil options we used to have! Obtanium, RCS (Renton Coil Springs), Ti Springs, and some others. I think you might.. with a big fat maybe… be able to order some RCS springs still.
In my opinion, EXT ones look very good and are light enough, and you need a reducer to use them on fox/canecreek/dvo which I believe is the same for a bomber.
Check out:
https://helixcoildesign.com/
Who is Alex Volokov?
https://www.pinkbike.com/news/tags/alex-volokhov/
K. So who is Alex Volokov?
Maybe this example will clarify;
If you have a PUSH SV8, and a Fox DHX, it is easier to change the base valve tune on the fully shimmed DHX, and there are many more options available, than the poppet system of the SV8.
The base valve on the DHX is comprised of 1/4" ID shims, which are very abundant and easy to source. In addition, a ring shim could be added to provide a pre-loaded setup, again with multiple levels of preload available. The number of potential base valve tunes is numerous; straight stack, preloaded stack, even a cross over stack is possible to install. Not saying that they are all good or will even work, but the options are numerous.
The SV8 base valve options are limited to what PUSH alone offers, or is willing to sell to the end user. Which seems like perhaps only one other option?
This is what is meant by a fully shimmed base valve having a greater tuning potential that an poppet valve system. A poppet valve system is limited to what the shock mfg offers, a fully shimmed system is not limited in this way. Does that make sense?
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