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IMO setting volume spacers is more faff - you have to open up your fork repeatedly to get things dialed. I totally get it when you say that triple air chambers can be hard to pump up, but I find that's not really a problem if you use a high-PSI shock pump.
I totally see what you mean. I’ve had my ERA fork for well over 2yrs and I’m still trying to dial in my air spring 😂 luckily for me I’m a huge tinkerer.
Yeah its definitely good for the people who like spending time with it! Just would be better as an aftermarket upgrade (1st or 3rd party) for most people instead of the standard spring
Well you could argue that most people who buy an ext fork know full well what it is they’re getting into. I’d much prefer 3 chamber air spring over standard token setup. I also wouldn’t want to have to buy it aftermarket if I’m already buying a high end fork like this. Now if three chamber springs made it onto oem then ya I could maybe see your point.
what is your opinion on a damper setup that allows the rider to keep LSC completely closed off without issues of harshness and then just dialing in however much HSC is needed for the type of trails your riding? I’ve been riding my ERA like this for some time now and haven’t experienced any harshness with LSC closed off to -1
My experience has kind of been the opposite - a lot of high end buyers are happy to pay the money because they expect something that "just works", which is why about 90% of my elevensix customers never turn a click on the adjusters- it just runs awesome for a year until its ready for a service and send it in. They are aware it could maybe be fine tuned another 5% better, but part of the cost of it means you get something that is really really good straight out of the box.
Personally I feel like time and money are the same thing - if you spend a bunch of money and then also spend a bunch of time setting it up, its no different to paying extra money on it. And that's cool! Tinkering is fun, and a huge part of why people get in to any hobby, but I think the high end products work best when they can be delivered ready to go with minimal effort from the customer.
As for running the LSC closed (or -1) - its not really something I can see a benefit to. It might be functional with certain types of high speed valve, but in use most dampers need at least a small amount of free bleed to allow oil flow during high frequency direction changes. Even with a light shim stack or spring preload there is a degree of pressure build up before it opens, and residual pressure that doesn't balance out once it closes which will usually lead to harshness or reduced grip. If anything I would usually prefer fixing the high speed damping at a certain rate then fine tune with the LSC dial as that is where you spend much more time so is more useful for fine tuning
I may be wrong here because I have no experience with the Era forks but usually, LSC is just a preload on a shim stack, so my understanding is that it is always regressive once you pass the point of overcoming the preload threshold. Thus LSC is similar to adding preload to a coil shock, if you are using a lot of it, it probably means your spring rate is not correct and you are instead adding something similar in effect to stiction in order to give yourself more support. But I guess at the end of the day if it feels the way you want it to feel then who am I to judge 🤷🏻♂️
LSC is pretty much always free bleed adjust, spring preload over shimstack or poppet valve is HSC.
Thanks Jakub_G, if that is the case then gladly please ignore my ramblings
https://podcasts.apple.com/us/podcast/demystifying-mtb/id1634499448
Jono and friends have plenty more insights for you over on this podcast. Definitely a wealth of info to listen to. Appreciate you taking the time to do this @TheSuspensionLabNZ
hopefully they are on Spotify or whatever for Android as well
Confirmed available on Google Podcasts.
Thanks for the share! Yes it is on spotify too - Matt & Rohan are super smart guys themselves, but have been getting a bunch of interesting people you might not normally hear from on their podcast. Taylor from Radic brakes is another one I recommend!
https://ep1.pinkbike.org/p5pb25570007/p5pb25570007.jpg
More evidence Jesse runs his fork real soft--as has been noted the past two seasons. ~70-78% travel from a nose-wheelie on flat ground.
Sorry to say but that proves exactly nothing. And using ca. 130mm while doing stoppie isn't wild by any means.
Are you sure I can't cut a travel spacer out of a new 2023 Super Deluxe with HBO?
I've got a 2023 Santa Cruz Megatower and a new 2023 RS Super Deluxe Coil with HBO that's 230x62.5mm. The Megatower listing says it's okay to run with 65mm shocks for 170mm travel instead of the stock 165mm. RS says I can't chop the travel spacer out because it will mess with the HBO, but is that really true for 2.5mm?
My crude math: stock HBO needle activates at 80% of travel, or 12.5mm from the end of the stroke (12.5/62.5mm = 20%). Cutting out a 2.5mm spacer means HBO would kick in 15mm from end of stroke, but stroke would also be 5mm longer, so now HBO would be kicking in at 23% (15mm/65mm = 23%).
Making the HBO activate at 23% from bottom out doesn't seem like the end of the world vs. the stock 20%. I think the air shock version kicks in at 25% anyway. Does that math check out or am I way off base here? Or are the other internal architecture problems inside the new Super Deluxe that I'm not aware of that would make this a problem?
The issue is you could bottom out the shock on the HBO cup/plunger instead of on the bumper, metal to metal contact is not very good in suspension components in general
https://www.youtube.com/watch?v=24-yB4Setus
Mandell mentions in this video that you cannot cut out that spacer with HBO units. Your math likely checks out, but that's what RS is saying.
Thanks all, I watched the Mandell video and yes indeed, it sounds like everything is crammed in there real tight and the shock relies on an exact amount of space between the two damping circuits at bottom out. Indeed, I don't want them to crash into each other because I allowed an extra 2.5mm of movement. Glad I asked, because that 2.5mm spacer was looking real tempting to cut.
If this was posted 24 hours earlier I could have had an exact answer for you
I had one completely in pieces and did test out inserting the piston/shaft assembly without the sealhead or bumper installed. It reaches a hard bottom (which is probably the HBO piston hitting the end) right around where the very end of the stroke would be, so there is very little room to play with there! I didn't take any exact measurements but this was with the shortest piston bolt fitted so I would be pretty confident if it was any longer you would be getting something contacting at bottom out.
Another job this week was also fitting the correct piston bolt for someone who had already cut the spacer out funilly enough
I did a little dive through the spare parts catalog and the service manual just to refresh myself on the HBO implementation that RS is using here. This seems like the most standard hbo implementation that I've seen, where it's a secondary piston with a bleed bypass and not the less common, needle style hbo. Intuitively, the relation of the secondary piston and the depth that it travels into the HBO receiver (for lack of a better way to refer to it), needs to remain constant despite the changes in travel.
At any rate, the parts catalogs confirm the fact that you'd need to swap out what RS is calling the "bottom post". Each travel change kit for the RS Coil that have HBO, include a "travel reducer, bottom post and bottom bumper". Those are referred to in note 15 in the below service manual cut sheets. This would need to change in stack height by 2.5mm in order to adjust the HBO engagement.
All great info! Thanks for demystifying this for me a little. Sounds like the bottom post (#15 in the diagram) has to be matched with the travel reducer to keep the check valve assembly from bottoming out in the shock body. Figure 34 at the end really shows how things are lined up inside the shock
Helpful post for me as well as I have a 205x60mm 2023 SD Ultimate Coil on my Transition Patrol for 160mm rear travel. I bumepd my 38 from 160mm to 170mm this spring and wanted to do the same with my coil but will wait until it needs a rebuild and ask SRAM to change the necessary parts.
Hey,
The DHX/Float X doesn’t look to have check shims or a rebound check plate.
I’m wondering why they use the check shims and check plate on the super deluxe?
Cheers
The DHX/Float X does have a check valve built in to the underside of the piston bolt- there is a shim under there (drawn in blue) that allows flow on rebound but closes on compression. I think its more common on shocks like Fox and Rockshox because they usually have a wide range of rebound adjustment, so if there was a lot of free bleed there would be a noticeable effect on the compression. Something like the Elevensix has evolved to not use a check valve (which is used to) because the rebound circuit is smaller and has very little effect on compression damping.
I think rockshox has different options because they have a few wildly different tunes (from digressive to extremely progressive) so it would keep the range of adjustment and feel in line with desired characteristics. It doesn't exactly add damping but a stiffer or preloaded check valve helps things like a digressive tune close faster at the end of the rebound stroke.
Legend, great answer and much appreciated.
Out of curiosity is there any exploded views of the Elevensix shock, can’t seem to find anything online. Just to see out of interested.
Many thanks again!
None that can be shared as far as I know, TF tuned did a tear down of one recently that lays it all out though - https://www.youtube.com/watch?v=6Uuka3Z0Vw0
There are images of the compression valves around on the internet as well which is the only part they didn't go in to
Afternoon,
Can someone confirm the use of the lock shims circled here. I assume they are used for “blow off” incase the shock encounters a hit while it’s in the lockout position?
Kind of, in reality there is no lockout, when "lockout" is on it simply directs the oil through those shims so it's an extra compression shim stack, compression needle assembly seems to cover different ports on the piston so either oil gets through shimstack or bypasses it. In practice there will be always some flow through this stack but it may be stiff enough to make this flow minimal utill a strong hit. So basically yes, but I would not call it a lockout, it's just super high compression mode.
Yeah thats bascially it, the backside of that top lock piston is dished so those shims are preloaded to create a threshold of where the shims open and blow off. The lowest shim you circled is the rebound check shim though - that prevents oil flowing through the rebound circuit on compression. The top 2 are the lockout tune, and I think they usually have a couple of different options there depending on how much platform the rider or bike is after
So apologies if this isn’t the proper thread, and if the terminology I use doesn’t quite work. Happy to clarify if needed.
I have a couple of questions:
1) For all you suspension folks, do you retune suspension when you change wheels/tires/tire pressure?
2) if all components in the front suspension sums to 100%, what percent do wheels and tires contribute? For the rear?
3) are wheels and tires primarily springs, or are they also dampers? If they are dampers, are wheels speed- or position- sensitive? Tires?
Seems appropriate to me!
1) not exactly-Because I recommend having tyres dialled in with appropriate casing, width and pressure first and suspension second. They both contribute to the system but in quite different ways so if you changed tyres then needed a suspension change it would mean you didn't have an appropriate tyre before. In reality it might not always work that way - I always say tyres are criminally misunderstood so its hard for people to pick the best tyres from the start and you might need a little bit of back and forward. Personally I think each rider/application has a range of widths and casings that are suitable and you can change within that window and shouldn't really need to alter the suspension to suit, unless for example you were going more XC with faster tyres you would probably want firmer more efficient suspension too. But it wouldn't be mandatory
2)Depending on how you quantify it I could probably get some actual numbers but in rough terms I would guess performance comes from 45% tyres 45% suspension and 10% wheels. The tyres are the only thing connecting you to the ground so everything goes through them. Without good tyres everything else further up the chain is compromised! I would always take really nice tyres with average suspension over good suspension with basic tyres. The wheels make a small amount of difference in terms of giving the tyre a stable platform and having an appropriate amount of flex but they aren't going to be a deal breaker either way unless you go too extreme in width or weight. I would say its pretty similar front and rear - up front maybe the tyre is fractionally more important since things like vibration are more noticeable but I think people underestimate how important the rear tyre and suspension is. Because of the way tyres generate friction with respect to load, theoretically the most amount of grip you can have is when both tyres have equal amounts of load on them, therefore they should both be optimised as good as possible. A lot of people say the rear "just follows the front" so don't worry too much about the tyre, suspension or brake choice but I don't agree with that. If you start with a 50/50 weight split and move your body forward to be 60% on the front wheel, you actually only have something like 55% of the grip and the rear might be 43%, or 98% of the peak grip available. Rubber has a non-linear change in friction coefficient as you increase the load on it.
3)Tyres are mostly springs with a small but noticeable amount of damping. Your smooth surface rolling resistance comes from the damping in the casing so it is important but they are mostly treated as springs. Thicker tyres and softer rubber normally have more damping and its hard to say if I would call it position or speed sensitive. Wheels are effectively just springs in most practical terms
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