Bird Aether 9 – better handling?

I’m after some advice please.
My first full suspension bike was a Bird Aeris Mk 1. Pikes (160 mm) and RS Monarch on the rear. I loved the bike – it could handle everything from XC to DyFi bike park. Unfortunately the seatstay failed.
Bird offered me an Aether 9 which seemed the obvious replacement (and a chance to go 29″). It’s got Pike Ultimates (140 mm) and a RS Super Deluxe Ultimate on the rear.
However, I’ve not fallen in love with it. The bike feels very ‘rigid’ – there’s minimal travel at low speeds. Even when the going gets tough it’s not very forgiving or plush. I’m just back from a week at Ride Southern Spain. At times it felt out of it’s depth.
Am I expecting too much from it, or are there improvements I can make?
The front forks had a full service before the trip. The technician removed a token and I was getting full (100%) travel. So, I think all is OK at the front.
I wonder if the shock is to blame?
Appreciate any thoughts/ideas.

Lighter compression tune on the rear ?

Did you set the rear shock lever to fully open?

It does sound like the rear could do with a tune of sorts.

My aether 7 with a coil felt bottomless until I went to

dyfi where it felt out of its depth, it’s not meant to

be a DH bike after all!  Then the aeris 9 felt exactly the same to ride just able to tackle even bigger features and handle

speed better. So I’d say you probably need to check the shock setup etc.

There’s quite a few things you could try.

Have you asked Bird though? They’re quite helpful and happy to discuss setup, I’ve found.

And my experience with my Aeris 9 is that they don’t always ship bikes with the right shock tune.

Thanks for the responses.
The shock was definitely in the open position (just been to double check!).
I did let some air out on the trip and was getting about 90% travel.
I’ve been on the RS Trailhead site to look at settings. All seems about right for my weight etc.
The site lists a ‘megneg upgrade kit’ for my shock which looks like it could be worth exploring?

I had an Aether 9. Despite what Bird say, it’s a trail bike.

I did what I could to make mine more capable, including fitting an X2 Float and 150mm 36, but it was not right and seemed to have a suspension tune that was focused on minimal movement around the sag point. Great for trail centres maybe, but not ugroomed natural trails IMO.

In the end I moved on to something more appropriate for my riding tastes.

You may find this useful.

https://singletrackworld.com/forum/topic/new-bike-day-and-first-ride-bird-aether-9c/page/4/

People have been nervous before with th Aether 9 and not just me.

Can you find a video of the kind of trail you’re finding it out of its depth on?

My Aether 7 felt awful at the rear, way too harsh, until I added a Megneg. So I would try that if I was you. They have a fair bit of adjustability via bands too so you should find a feel that you like.

Ultimately I went coil because I had one of those too but the Megneg’d shock found a home on my wifes Aether 7.

Like Surfingobo, the only time it felt out of its depth was at Dyfi but I still had a cracking day.

It’s also the bike that I had my best year of progression on.

Thanks for the link Scienceofficer – interesting reading.

Bikesandboots – here you go. Hard, fast and rather rocky in places…. https://www.youtube.com/watch?v=7pSL8yqv4vU

Appreciate your feedback on the megneg Mugboo, fitting one seems like a sensible (and affordable) starting point.

I’m not in the market for a new bike right now so would like to try and make the A9 work for me. I’ll also speak to Bird to see what advice they can offer.

Totally different bike, but I liked what the megneg did for me. Have a look on Bike inn, they’re £54 on there. Cheapest i could find when I did mine.

@rustychain sorry you’re not enjoying it – the progressive nature of the frame does make set up harder for sure. We’re restarting the shock tune days in 2025; you can come along and ride with our team for the day and get free tuning/changes during the day. Ive not set the dates yet but if you want to mail us happy to chat on what your current set up is (as well as check your shock’s running ok) and keep you up to date as we set the tuning day dates.

My pal has had an Aether for a few years now and pretty sure he has a Megneg fitted. Seems a popular mod on the Bird Owners FB group if your sticking with air. Plenty of people on 150s front but that’s probably marginal gains.

Conversely I’m loving my 9c, but I think this is more to do with my use and expectations though – mine’s very much built up as a light trail/xc bike (use the D word, if you must) with 130mm Pikes, Deluxe Ultimate and very fast rolling tyres. Essentially I wanted something that doesn’t feel like a drag on longer xc rides, but is still fun to cock about on and with modern trail bike type geo that looks after me when I’m writing cheques my limited skill set can barely cash. It didn’t aim for an Aether, but the recent insane sale prices led me to take a chance on it and it’s worked out better than expected. I like the support from the rear end and picking my lines through rough terrain, but then I also ride a hardtail a lot of the time. For bigger/rougher terrain though, it’s probably not the tool I’d use… I know there are others happily running 150mm forks, coil shocks and burly tyres on their Aethers and I’ve considered trying something like this, but I think that might take more from the qualities it has that it would add to the ones it doesn’t.

I had a bird aether 9 and fitted a megneg to it – it felt much nicer.
Before i always seemed to be tinkering for that sweet spot

The suspension was OK – but i found the that the really short back end and long front end did not work for me on really tight technical down hill trails.
At speed in flowing corners it was lovely.

Cheers Ben, I’ll get in touch. A shock set up day would be great.

I suspect the shock is stock so I’ve ordered a megneg from Bikeinn as a starting point.

Could you open up the shock and see if there are any volume spacers in ?

I have an early A9C and as much as I want to, I just don’t get on with it. To the point where I don’t really ride it, and it is a very nice spec. I struggled with setup, but also with a the front end wanting to collapse on me on turn in.

I have the same issue as you, the rear never feels plush or it is too soft. I have heard the MegNeg will sort it out, but I have given up riding for the moment, nothing to do with the A9C, more “life stuff” and some bad times on rides, so that has gone on a “maybe one day” list.

I did, however, have a test ride on a Aeris AM, one size too big, and it was great! A much more mature bike (IMHO). If I was to carry on riding I would probably look to swap out the A9C.

I should add my first bike was a Zero 29 and my HT is a Forge.

I really like mine, I don’t often get full travel at the rear, maybe 10mm left on the o-ring but perhaps I’m not riding hard enough. I did find a lack of support initially, wallowing through the travel at lower pressures but harsh at higher.

Could you open up the shock and see if there are any volume spacers in ?

This was my problem, I think it had a negative volume spacer in, so taking it out moves the curve towards a meg-neg. So I’d try that first.  Feels great now, don’t tend to think about it, but in hindsight I’d probably have got a coil shock.

I have a Formula coil shock on my Aether 9C and love it to bits. Like @benpinnick hints, progressive kinematics work best with a linear shock – megneg essentially makes an air shock more linear.

I’ve run mine with both a CCDB inline coil and a RS air shock. The coil feels better so stays on most the time.

I had the Aether 7 for a couple of years and loved it for everything but the rockiest uplift centres.

I was running a Fox DHX2 coil and a 150nm Lyrik and it was very capable – but at Antur in particular I felt utterly battered on it – where I hadn’t on a previous visit there in a Bird Aeris 145 LT (170mm front / 260mm rear travel).

I was going to move to an A9 or AM9 – but ended up with a Transition Sentinel. Over the rockiest stuff the extra travel is ace. Not as playful on slower stuff as the A7 though.

If you’re riding lots of rocky stuff I’d put a 150mm airshaft in your fork and at least try the megneg to see if you can get a setup you like more. If not, doing a frame swap with an AM9 shouldn’t cost you too much and the extra travel makes a difference. The older Pikes go to 160mm travel I think too.

megNeg on my A9a made a big and nice change from the std setup. Made it feel far more active and less rigid feeling. I used it with a 150pike and 150lyrik – later was nicer, but both worked well. I have since go at  longer travel bike so the A9a when back to pikes at 140mm.

The MEgNeg kit arrived yesterday so I stripped the shock down.
I was expecting to see a bottomless token or two fitted but there were none. Maybe that’s how they come?
I tried the Trailhead app but no mention of tokens.
Is it worth trying a couple to see how I get on? Or is it better to run without if I can get the set up right?

No, set the megneg up first, try it and then see. If you haven’t already added positive tokens, then it’s unlikely you will be now with the megneg as you’ll be running higher pressures.

Adding tokens would make the suspension more progressive, and your problem seems to be related to it being quite progressive anyway.

As Yak says, add the MegNeg and see how that goes – do report back 🙂

Thanks both, I’ll crack on with getting it fitted and tested.

How have you got on with it?

I started off with mine with the biggest negative spring volume possible (no bands in the megneg can) – I found that was too stiff / harsh.

Ended up with 2 bands in there and it was a decent upgrade over standard. No bottomless tokens in the positive spring.

I’ve fitted two bands as a starting point.

So far I’ve only been able to test ride it in the street. First impressions are positive, when I pump the bike it feels more plush.

I’m still trying to dial in the right pressure. Currently at about 220 psi which is a tad over 30% sag (the Aether 9 data sheet recommends 25-30%).

Has anyone tried the Rockshox Linear XL air can on their Aerther? It has a larger positive chamber rather than a larger negative air chamber, but seems to promise a similar behaviour change as the MegNeg, but with more adjustability at the end of the stoke.

As I recall, removing bands makes it plusher around the sag point, ie more linear in that part of the curve, and also ramp up more at the end. I ended up with no bands (and no skills either).

Has anyone tried the Rockshox Linear XL air can on their Aerther? It has a larger positive chamber rather than a larger negative air chamber, but seems to promise a similar behaviour change as the MegNeg, but with more adjustability at the end of the stoke.

I have, its a recommended upgrade from me, for 2025 Aethers are moving to the XL can.

What inline air shock (no piggyback as I want a bottle on a medium) options are there, and what to choose between them with the Aether 9 in mind?

RS Deluxe

RS Deluxe with Megneg can

RS Deluxe with XL can

Fox Float

Cane Creek DBAir IL G2

Manitou Mara Pro Inline

The Cane Creek DBil is meant to be good although not used one myself. Cotic fit them quite a lot – a mate has one in a Jeht and I think he’s found it decent.

I’ve run a deluxe with a megneg and it was decent – I’d try and get an ultimate if doing that so you have some extra compression damping adjustability over the more basic versions.

It’s not really relevant but I ran a Cane Creek DBIL on cotic rocket when I had one. It’s really good and can be set up almost anyway you want. More adjustable than most inline shocks with independent high and low speed compression and rebound damping controls. Handy app to get you going too. When I needed some spare parts for it, I found Jtech had everything so ok to keep it going.

It’s the Deluxe Ultimate with standard air can that I have already. 145psi for 75kg rider, haven’t added/removed any spacers since it came from Bird. No real problems with it but I definitely run more LSC/HSC on my fork than the shock is capable of, which makes the bike tail squatty on some jumps/drops. The 3 position compression adjuster doesn’t do anything noticeable really, the bike has a lot of anti squat I understand for climbing and even more with the 30T chainring I run, so doesn’t rely on compression damping to avoid bobbing.

I think I’m way more sensitive to having a good fork setup than shock, as it affects hand/arm comfort, pitching, and loading the front to generate grip. But still interested in exploring shocks.

I have a Float X (has a piggyback) on my ebike, it has a useful range of compression damping but still a single adjuster.

So I think that just leaves the Cane Creek DBIL.