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So Rockshox are at it again with air spring changes. Here's a recap.

The 2015 Rockshox Pike A1 and 2016 Lyrik B1 used self balancing air springs where positive and negative chambers were equalised by a notch inside the stanchion. This notch met the air seal near top-out which filled the negative chamber but didn't pressurise it higher than the positive.

These early forks were plagued with air leaks from the negative chamber into the lower legs. Caused mostly by too much clearance between the air shaft and the black plastic seal-head. So shaft deflection could burp the seal and pressurise the lower legs.

This is why people were sliding zip-ties down past fork seals.

Rockshox released a new seal-head with bigger seal to counter this leakage. It worked and came in most 200H service kits. Vorsprung have identifying pictures here: https://vorsprungsuspension.com/pages/luftkappe-installation-setup

A very good and popular upgrade for these was the Vorsprung Luftkappe. This replacement piston does three things.
1. It moves the piston seal down relative to the equalisation port to create a higher negative compression ratio. This reduces top-out forces to zero.
2. It increases negative volume through a domed cap (which reduces positive volume as a side-effect) so the negative spring effect extends deeper into travel.
3. It removes the need for a top-out bumper which further increases negative air volume.

The net result of these changes was a straighter air-spring curve. The first half of the stroke became a lot more linear from top-out through the midstroke. Using higher air pressure but getting better small bump response and mid-stroke support.

At this point in time the Debonair name was being used by Rockshox in their rear shocks (with high volume, dual layer, positive and negative air-cans) and also for the Lyrik and Yari (same chassis) which had longer stanchions and 10mm longer negative air chamber than the A1 Pike.

Rockshox took this opportunity around 2018 to release their first Debonair upgrade.


They replaced the, previously removable, air piston with a riveted on plastic moulding with air channels to allow negative air to flow into the shaft. Using that internal volume to increase negative air volume. The air seal position stayed in much the same location keeping the compression ratio and positive/negative balance pretty much the same (near zero at top-out).

The big engineering change was the stanchion end-cap seal-head. It was now machined aluminium (more precise than moulded plastic) and featured a DU guide bushing to keep shaft/seal alignment and prevent leaks to negative. This allowed less seal crush which reduced friction.

All round a good upgrade. Doesn't have the same volume increase or compression ratio as a Luftkappe but was a drop-in upgrade that people bought in huge volumes to solve their forks previous problems. Solid win for Rockshox.

The big criticism of this Debonair was the forks wouldn't sit at top-out. Just the weight of the bike would sag it and Rockshox own sag indicator stanchions had their customers getting concerned they'd got less than they paid for.

Roll on today with Debonair 3 (that's my name, not RS's).
https://www.pinkbike.com/news/first-ride-rockshoxs-updated-debonair-air-spring-pond-beaver-2020.html


There are two physical changes to this air shaft over Debonair 2.
1. Longer shaft foot.
2. Higher end-cap seal-head.

The longer shaft foot does exactly one thing. It makes the shaft longer to move the lower legs down. This fixes the customer concern that their zero point has eaten a few mm of travel.

The higher placed end-cap seal-head is required to fit the longer shaft foot. Without that the longer shaft foot would hit the end-cap at bottom-out. Causing damage, shock and noise. In addition RS have taken more negative volume. Ostensibly to reduce positive pressure ramp up in the lowers during deep compression.

The downside to the higher end-cap is a reduced negative chamber volume. Expect this to be ignored or glossed over in initial releases.

The expected ride changes:
1. The fork will sit higher on it's travel indicators solely because the lowers have been spaced down.
2. The lower negative volume will make the fork firmer off the top and ride higher still.
3. Softer mid stroke (less support) due to the reduced negative volume.
4. Less progressive due to lower leg pressure build-up? That's going to be hard to isolate on ride tests.
 

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Looking at the pinkbike initial impressions, it looks like something I am going to get. I would love for my forks to ride a little higher than they currently do without having to over pressurize them.

The bummer is I just did the lower service for both my lyrik and pike so when I order these I will have to pull them again. Maybe I can put some tape or something on the bottom holes so all the oil doesn’t run out and I can just swap this part.


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I have a "2019" pike with the grey air piston and red anodized seal head. I'm assuming this is version 2 but would require the whole kit?

Probably going to see if I can install a Luftkappe on a 2016 air shaft that I have lying around.
 

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Maybe this will get rid of the ~5mm worth of dead travel on my Yari. I recently did the DebonAir upgrade on my A1 Yari. The fork would never return to full extension. I was always able to pull the fork up another few mm's. I juuust replaced the Yari with a DVO Diamond. The DVO always returns to full extension and has no dead travel. The DVO also rides higher in its travel.

Maybe I'll hang onto the Yari and get the upgrade to my upgrade.:rolleyes:
 

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If you want more travel and aren't already running 180mm, you could just try to get your hands on one of the previous Debonair springs in the next size up if they're still available.
 

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This is kinda funny because the previous Debonair spring was quite similar to the Luftkappe and Vorsprung have this in point 10 of the FAQ: Who is this NOT suited for?

" If you're anal about your fork having an exact (but rounded-to-the-nearest-10mm) amount of travel. "


Sounds like Rockshox have made things worse because so many customers don't understand their fork. Kinda like when they went to solo air over separate positive and negative.
 

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Just ordered 2 of the foot nut/seal head kit.

That is an interesting idea of just bumping up the travel by 10mm to account for the lower ride height. But since the price of the 2 upgrade kits was almost the same as a new air spring, I figured the new kit was the way to go.


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The good this is that you can get the footnut and lower seal head separate.
Yeah, I may get around to just buying the seal/nut kit and giving it a go since it's not expensive.

I'll wait and see what real world experience/reviews are later on.
 

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Maybe this will get rid of the ~5mm worth of dead travel on my Yari. I recently did the DebonAir upgrade on my A1 Yari. The fork would never return to full extension. I was always able to pull the fork up another few mm's. I juuust replaced the Yari with a DVO Diamond. The DVO always returns to full extension and has no dead travel. The DVO also rides higher in its travel.

Maybe I'll hang onto the Yari and get the upgrade to my upgrade.:rolleyes:
Similar situation w/me with recent upgrade re: the dead travel.
Also, explains why the height of my bike's front end/handlebars didn't really change when I put in the Debonair for 130mm, vs my orig 120mm.

BUT, I'm very happy with my Yari now, on my hardtail. Love it, despite my original confusion.
 

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So Rockshox are at it again with air spring changes. Here's a recap.

The 2015 Rockshox Pike A1 and 2016 Lyrik B1 used self balancing air springs where positive and negative chambers were equalised by a notch inside the stanchion. This notch met the air seal near top-out which filled the negative chamber but didn't pressurise it higher than the positive.

These early forks were plagued with air leaks from the negative chamber into the lower legs. Caused mostly by too much clearance between the air shaft and the black plastic seal-head. So shaft deflection could burp the seal and pressurise the lower legs.

This is why people were sliding zip-ties down past fork seals.

Rockshox released a new seal-head with bigger seal to counter this leakage. It worked and came in most 200H service kits. Vorsprung have identifying pictures here: https://vorsprungsuspension.com/pages/luftkappe-installation-setup

A very good and popular upgrade for these was the Vorsprung Luftkappe. This replacement piston does three things.
1. It moves the piston seal down relative to the equalisation port to create a higher negative compression ratio. This reduces top-out forces to zero.
2. It increases negative volume through a domed cap (which reduces positive volume as a side-effect) so the negative spring effect extends deeper into travel.
3. It removes the need for a top-out bumper which further increases negative air volume.

The net result of these changes was a straighter air-spring curve. The first half of the stroke became a lot more linear from top-out through the midstroke. Using higher air pressure but getting better small bump response and mid-stroke support.

At this point in time the Debonair name was being used by Rockshox in their rear shocks (with high volume, dual layer, positive and negative air-cans) and also for the Lyrik and Yari (same chassis) which had longer stanchions and 10mm longer negative air chamber than the A1 Pike.

Rockshox took this opportunity around 2018 to release their first Debonair upgrade.


They replaced the, previously removable, air piston with a riveted on plastic moulding with air channels to allow negative air to flow into the shaft. Using that internal volume to increase negative air volume. The air seal position stayed in much the same location keeping the compression ratio and positive/negative balance pretty much the same (near zero at top-out).

The big engineering change was the stanchion end-cap seal-head. It was now machined aluminium (more precise than moulded plastic) and featured a DU guide bushing to keep shaft/seal alignment and prevent leaks to negative. This allowed less seal crush which reduced friction.

All round a good upgrade. Doesn't have the same volume increase or compression ratio as a Luftkappe but was a drop-in upgrade that people bought in huge volumes to solve their forks previous problems. Solid win for Rockshox.

The big criticism of this Debonair was the forks wouldn't sit at top-out. Just the weight of the bike would sag it and Rockshox own sag indicator stanchions had their customers getting concerned they'd got less than they paid for.

Roll on today with Debonair 3 (that's my name, not RS's).
https://www.pinkbike.com/news/first-ride-rockshoxs-updated-debonair-air-spring-pond-beaver-2020.html


There are two physical changes to this air shaft over Debonair 2.
1. Longer shaft foot.
2. Higher end-cap seal-head.

The longer shaft foot does exactly one thing. It makes the shaft longer to move the lower legs down. This fixes the customer concern that their zero point has eaten a few mm of travel.

The higher placed end-cap seal-head is required to fit the longer shaft foot. Without that the longer shaft foot would hit the end-cap at bottom-out. Causing damage, shock and noise. In addition RS have taken more negative volume. Ostensibly to reduce positive pressure ramp up in the lowers during deep compression.

The downside to the higher end-cap is a reduced negative chamber volume. Expect this to be ignored or glossed over in initial releases.

The expected ride changes:
1. The fork will sit higher on it's travel indicators solely because the lowers have been spaced down.
2. The lower negative volume will make the fork firmer off the top and ride higher still.
3. Softer mid stroke (less support) due to the reduced negative volume.
4. Less progressive due to lower leg pressure build-up? That's going to be hard to isolate on ride tests.
What a great explanation that is easy to understand. Thank you for that.

From my perspective, I'll stick with my Debonair. I did remove the negative chamber bump stop and that combined with the addition of low friction Push seals (already has a great Avy cartridge) made the fork down right coil like. I mean it has no stiction, but it has better mid- travel support too.

Don't care about the 5mm of fork sag, it doesn't matter to me and I still run the same 22% sag based off the full 160mm travel.

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At 25.00 and an easy change back if I am not impressed I figure I’ll give it a try. I ordered one today but who knows when they’ll actually be available. I still think this may just be a “fix” for people obsessed with looking at their fork topped out stationary but I’ll see what my own opinion is after trying it.
 

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Seems like a down grade, hope they keep making the current version (debonair 2) and not just the new one.

If not, maybe there is room in the market for an aluminum piston version of the debonair 2. Seems like there might be some opportunity for reducing friction a bit over the plastic piston?
 

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My LBS suggested me to upsize my fork so the dead travel doesnt matter anymore. Lyrik loses 7-9mm of travel; Pike around 3-5mm.

I took 170 Lyrik for my bronson. After dead travel, I get around 163mm.
 

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given we ride with sag who cares if there is a few mm of travel lost when the bike is leaning against a wall or am I missing something?
You are probably correct. If you are 25% sagged when you initiate travel who cares where your starting point it from. People try to understand things in static terms because that is easier to understand but your starting travel and even your sag % is just a static number. The dynamic ride height is probably most important.
 

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So Rockshox are at it again with air spring changes. Here's a recap.

...

The expected ride changes:
1. The fork will sit higher on it's travel indicators solely because the lowers have been spaced down.
2. The lower negative volume will make the fork firmer off the top and ride higher still.
3. Softer mid stroke (less support) due to the reduced negative volume.
4. Less progressive due to lower leg pressure build-up? That's going to be hard to isolate on ride tests.



I know it's still speculation at this point, but you don't sound excited about it.

Sitting topped out few a few mm sagged doesn't sound like any kind of performance gain. If anything, it would make top out while riding more harsh, right?

As far as the negative volume reduction, I'm curious what kind of % change this will be. Hard to get an accurate figure without a very accurate CAD model, since the negative volume isn't a simple shape.

Equalizing the negative chamber at top out vs sag? It's hard to see a benefit from that either, besides removing the need to bounce the fork while adding air.
 

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https://www.bicycling.com/bikes-gear/mountain-bike/a32058013/rockshox-2021-debonair-updates/

"With previous generation air springs, there would have been a small but noticeable downwards spike in the spring curve where the air changes across the dimple"

Not sure if this is a problem but decreasing negative chamber seems to be questionable.

On a negative chamber where the pressure cannot be chosen, i also think it was designed about a specific travel (160) and weight. On heavier persons it might be too small. I got an calc sheet where you can see the optimum of the air spring curve close to a steel spring is at an specific psi and amount of token.
 
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