Just finished my custom Aeris 9 build up and this is my third FS from Bird. Have ridden the heck out of their 120LT and the AM9.

I cant just yet tell you how the A9 performs on the trails but the frame has gone through somewhat of a change when comparing it to the AM9. The AM9 was a superb all mountain/enduro bike but with a little bit more flex and a lower weight. Soooometimes I had that lower alloy weight back in my mind when ploughing (+200lbs). The A9 has been beefed up, better geo, changeable geo ( long/short CS, 29" or 27,5" rear with a linkage change*, 160 or 180mm rear travel with a linkage change and 160 to 180mm travel up front.

* The mullet linkage is in the testing as far as I know of.

Frame quality is good and no issues with bad threads or crooked BB face and the same with the face of the head tube. The frame finish is not like you see on Santa Cruz.

Just by doing the carpark test the A9 susp feels even more balanced than the AM9 and that thing is a killer bike with superb geo. The steeper ST was noticeable too and in a good way. But first serius ride is coming up.

 

Looks super sweet, and more ride impressions now that you've had it a while?
Thanks!

 

So far turned out to be a very nice bike a tiny bit more planted on the trails compared to my old Bird AM9 RRR. The A9 bobs just as little as the AM9 but climbing feels better - could be due to the steaper SA. The bike feels stiffer and let you feel the tires work more in high g turns.
The bike is setup with 25-27% sag in the front and 30% rear.

I dont think it's night and day different to the AM9 with a RRR linkage and MegNeg. An AM9 v1 or v2 without RRR and MegNeg (cant comment on Fox, CC or other) then you would feel the difference much more.
The rear is noticeable stiffer and you feel the front being more slack. The balance of the bike is still VERY good and confidence inspiring. It's a long bike but with the low'ish BB it really likes to corner but you have to man handle the bike when comming in hot for some bermed S turns.
I can weigh the difference in weight but I cant tell on the trail (around 800g heavier compared to my old AM9)

As pictured the weight is 15.6kg/34.39lb.

I use the Aeris 9 as an allrounder but from the more janky stuff to Alp adventures. I still wanted it to work with open fast'n flowy blue bermed trails and opted for the air shock to give it some pop over the coil. Coil makes no sense here on my local trails.
To give the most fair comparison I should use the same rear shock as I also feel the new SD Ultimate RC2T is an upgrade over the "old" SD Ultimate RCT. Both running same tune L/L1

 

How many Rubber Bands did you run in the negative chamber for the am 9?

 

Ran 0 Volume Reducers and 2 red bands

 

Thanks I still trying to figure out the right Setup with megneg at the moment i have 4 Bands and 0 token at 73kg rider weight

 

There was a lot of writing back and forth on the Bird Facebook page when the MegNeg first came out and the vast majority rode the MegNeg like me and at 30% sag.

 

Any more feedback on the Aeris 9? Is it comfortable to pedal all day? Does it mellow out easy trails too much?

 

It's very comfortable to ride and is still just a balanced a bike like the AM9. I dont find that the geo of the Aeris 9 favors one thing more than another. You just feel at home on the bike and that gives me more confidence to push my riding more. BUT... I also took the bike out on a very mellow blue trail and that worked out just fine. I normally take my trail HT out on that trail but wanted to experience the Aeris 9 on that trail. Worked out just fine and I really didn't think about I rode a FS - it's that good of a pedal muncher.

But what bike do you compared it to?

 

I ride a v1 Transition Sentinel now (with a cascade link), but am looking for something with longer chainstays and a more dropper post insertion depth

 

I actually just got an Aeris 9. As mentioned above I'm coming from a v1 sentinel. I'm still getting the Aeris 9 dialed in, but overall it's an excellent bike. The handling is a lot more balanced; you don't have to weight the handlebars as aggressively as you do the sentinel. The rear suspension seems very good so far. It's got a lot of traction and pedals well. I'm running just over 30% sag, and I have not bottomed it yet, but I may have to increase the pressure. For a fork, I'm running a marzocchi bomber z1 coil.
The RS superdelux isn't the best, it weeps a lot of oil, and any amount of LSC just adds harshness. But it does feel OK for the time being. I may get it retuned, as there are a lot of suggestions for improvement (I feel it could use a bit more HSC) but I may also go with a coil shock too.
My only gripes with the bike are a lack of a good chainstay protector (I hear nukeproof mega ones fit, it would be nice if they just shipped those with it, they are like 10 dollars), they shipped a lizardskins velcro one which sucks for a bike like this. The water bottle location also isn't great with the RS superdelux. The resivoir is long on that shock, and it hits the water bottle. Bird has an angle bracked which also moves the bottle back a bit. They should just ship these with every bike IMO. I made a little bracked out of some aluminum stock which does the same thing, and a bottle fits, but the sentinel fit a bigger one easily.
The only other gripe I have as a buyer from the US is our payment systems don't work well when trying to buy stuff from small companies in different countries. This is not bird's fault at all, but in the UK it seems most purchases like that are done by bank transfer, whereas we use cards. It took some back and forth with my bank to finally get the transaction approved.
That brings up another good point. Bird has been really responsive and very helpful! They were super patient with me when my bank didn't want to transfer funds, and answered a bunch of questions I had. The problems with the water bottle and chainstay protector are pretty minor considering how nicely the bike rides. I took it on a long cross country style ride today and had lots of fun on tight and twisty turns (this bike RAILS corners) but it also seems to be a very confident descender. I've been riding a lot of different bikes recently - Ibis Ripmo, Transition Sentinel, Fezzari La Sal Peak, Commencal Tempo, Pivot Firebird, Santa Cruz Tallboy, Santa Cruz Bronson, and I really like this one the best (the Fezzari was 2nd best). The handling balance is what make this bike feel great.

 

Check out the raw Madonna chainstay protector and the yt thirstmaster bottle. I use them on my aeris am 9.

 

@tstinchy

Sry, I totally forgot this post but i'm glad for you that you took the chance and got the Aeris 9. Balanced is the key word here. You should aim for 30-35% seated sag on the rear shock so it sounds like you're in the ball park.

Regarding CS protection Bird just released their own protection that should fit the Aeris 9, AM and AM9. But they didn't have any when I needed one so I got the RAAW Madonna protector and just to kill the chain bounce I mounted some STFU Trail too. It's now super quiet and I used to run STFU on my old bike so the looks dosn't scare me.

 

No worries at all! I started out with like 25% sag, and that was really harsh, with ~30% I am now it feels a lot better. For the chainstays I was able to get a protector that goes to a Salsa blackthorn. We'll see if it fits at all. The only issue with being in the US is that getting parts from the UK or Europe isn't that easy. If bird comes out with a better protector though, I'll try and get one of those.

 

Ben Pinnick from Bird says that their reference point is 35% seated sag as the travel changes a bit towards 30% when in normal rider position.
I'll through in a pic of the new protector on the new AM here.
BTW if you are on Facebook the "Bird Cycleworks Owners" group is a pretty good place to get answers and help quickly both from users and from Bird.

 

Untitled by Joost Nijland, on Flickr
Untitled by Joost Nijland, on Flickr

using mine in everything from the local simple xc style track untill the black trails in the alps. climbing is very good for how much bike it is. for the big trips i'm using the 180mm link combined with 180 mm front. normal is 180 front and 160 rear