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I'm considering ditching the hardtail and building up a Bird Aether 9 into a light weight trail bike. I have a Starling Murmur which does the bigger burlier duties but it sometimes feels a bit much for just a little razz in the woods or a more leisurely ride.
How many folk have an Aether 9 and what kind of build weight can you get one too without getting too silly with money? Looking at something like that GuyKes Flaremax build he did as my inspiration.
First ride photo
Luggage scales don’t lie
Ooh I can answer this one.
Just built up an aether 9 with the bits off my hardtail-
It weighs 33.7lb/15.3kg in this spec (ml frame)
Fox 34 rhythm
Mavic xa wheels
Slx brakes,1x11 shifter mech 11-46 cassette rotors 185f 180r
Tyres are mezcal 2.6 r with rimpact, vee flow snap 2.6 f
One up dropper 180mm
Charge spoon
Bars answer pro taper alu 785
Stem lovemud 35mm
Ergon ge1 grips
Nukeproof plastic pedals
Due to getting COVID only had 2 hours on it but did set a strava pb on a fast techy dh- previous fs was a calibre sentry with 20mm more travel both ends.
I’m impressed so far…
Actually I think I weighed it with deore 596 brakes and ride race face cranks. Maybe weighs a smidge less now.
If I was looking to lose weight I’d swap the bars for nukeproof carbon for £90 and go for a lighter front tyre. The internet says my wheels weigh 1900g but I don’t believe that for a minute. Also front guard I guess…
I've had mine about a month. It's awesome.
Pretty much the same weight as docrobster's but a different spec:
Large frame
Shock - Rockshox Deluxe Ultimate
Forks - Rockshox Lyrik Ultimates currently at 150mm, may drop them to 140mm but enjoying them so far
Wheels - DT Swiss M1900
Tyres - 2.5 Minion DHF and 2.4 Dissector
Brakes - Deore 4 pots
Shifter - XT
Cranks and Rear mech - SLX
Cassette - Sunrace
Seatpost - Bird's own 200mm dropper
Bar and Stem - Bird's own - 800mm and 40mm respectively
Grips - Raceface
Pedals - Nukeproof plastic
It's a fairly burly build, plenty of scope to reduce the weight (e.g. wheels, tyres) but I really like it for what I use it for. Climbs really well and descends amazingly.
Cheers both. I do quite like that in the raw finish and with some lightish wheels and tyres it might just do what I want of it.
Mine was 16.5kg* medium as collected (with sealant, without pedals). Pike Ultimate, Deluxe Ultimate, Deore, XM481/Pro4, bash guard, DHR2/Dissector, alloy bar.
I think that figure may well be out because a) it's 2.7kg more than the sum of the published weights of all its components, b) it's 1kg+ more than the above posters, c) BikeRadar had a higher spec one down to 14.8kg without pedals (that's 1.7kg lighter).
To save weight on the above I would take:
1. XM1700 wheels (-150g, £-45)
2. Lighter handlebar (-150g?, £+ not much for an alloy one, the Big Baw bar is 6061 alu, so is the RF Chester and that's a hefty 400g)
3. SLX (-200g, £+100?)
Bird have said on here the frame is 3060g without shock, no size specified. For comparison, Specialized claims the carbon Stumpjumper is 2280g in S4 including shock (350g?) so a ~2kg frame.
That does seem excessively chunky for a medium of that spec.
Frame weights can be found on the tech specs on their website.
It weighs 33.7lb/15.3kg
My AM9 with a coil is only 300g more, I don’t know if that’s heavy or my AM9 is lighter than I thought.
Frame weights can be found on the tech specs on their website.
For the am9 but not aether. Am9 medium 20g heavier than the above quoted 3060. More travel doesn’t weigh extra…
My mistake. Its the Aether 9C weight that are listed.
My Aether 7 is 32lbs almost bang on. Would imagine the frame weights are broadly similar so it’s just the wheels and tyres with more weight for the extra wheelsize.
Mines got a deluxe rt3 / 150 Lyrik / Codes / Pro4 hubs / xm481 rims / xt 12 speed cassette, mech and shifter / X1 gxp carbon cranks / carbon brand x bar / 210 Oneup dropper / dhf 2.5” exo / 2.6” slaughter grid with Rimpact. I reckon with a Pike and some carbon rimmed wheels with light hubs I could get down to near 30lbs. So I reckon with a similanbuild the aether 9 could be 31lbs.
The 9C frame is about 300g (0.6lbs) lighter than the 9A I think.
All those weights seem more in line with my Starling Murmur build, though in reality I'm guessing my build is around 34lbs without really trying to make it light. Reckon it's possible to get it sub 30 with a lighter fork, 25mm rims and faster/lighter tyres.
Specialized claims the carbon Stumpjumper is 2280g in S4 including shock
That is light but way out of budget. Any other frames worth looking into, Transition Spur looks good but also too much money.
I still think you need a Stage 4 like mine (28lbs with light wheels IIRC).
I still think you need a Stage 4 like mine (28lbs with light wheels IIRC).
Maybe maybe...
Demo ride offer still stands, if you bring your Starling.
🙂
The 9C is about 600g lighter than the 9A. I do need to weigh mine,
Build is:
9C Medium
Pike Ultimate RC2
Full SLX
Hope Pro 4's with XM481
Deluxe Ultimate
Unite Renegade and the rest Bird kit.
Hutchinson Griffus and Vittoria Agarro
I suspect I'm a smidge under 15.5kg
9c frame is not 600g less than the 9a frame if thats what you meant above.
M/l size 9a is listed at 2810g, a M/l V1 Am9 is 3000g and the M/l V3 AM9 3200g.
I think the 9A is pretty much the same weight as the V1 AM9 based on the FB group owners feedback. The A9c wasn't ever intended to be lightweight over other criteria.
The A9c wasn’t ever intended to be lightweight over other criteria.
Did they just want to make something more gopping then?
(Sorry, couldn't resist, so what was the intention then?)
Still seem to build up heavier than I would have thought, though I guess tyres and wheels make a big difference to weight and feel. The carbon one looks ok I think, I'd prefer if the downtube didn't kink like it did but i'm not willing to spend that much anyway.
You say your murmur is 34lbs but have you actually weighed it? What build kit is on it? Sub 30lbs is a tough measure if you have a heavy full suss frame to start with.
My steel Marino hardtail frame weighs 3.1kg with axle and seat clamp - I’ve just squeezed the full build at about 30lbs with a pike ultimate, gx Eagle drivetrain / code brakes / light wheels (erase components hubs and XM421 rims) / carbon bars / carbon cranks / exo casing tyres etc.
The Aether 9 frame is probably going to be lighter than the Starling given it’s alloy vs steel (unless the number of pivots really count against it). Plus the Aether has quite a progressive curve to make it pedal ok up hill - yet with the Horst link it’ll stay nice and active under braking.
I don’t think you’re going to get a much lighter frame brand new whilst staying around that budget.
You could check how much the Sonder Cortex weighs - that’s a short travel 29er that’s available fairly cheaply and frame only?
Not sure how much difference 300g bare frame weight is going to make in the real world. Heavier farts, etc
Compared to my previous bike, a porky calibre sentry, it’s easier to lift on to the roof of my suv to drive it to a trail centre which is what it’s designed for. Win win. 🙄
It rides nice and feels less like a steam roller than the sentry. I’m hoping it will simplify matters for me as I’ll have one bike for all my mtb riding rather than having to choose between, and keep running, 2 bikes with slightly different extremes of use but a large overlap in the middle. Other bike being the last fast forward I took all the parts off for this build…
I may relent and build up a rigid xc hardtail for winter though.
Re the op, looking at the geometry of a starling murmur I’d say the 9a is going to be too similar in feel and intended use. And not that much lighter.
You mentioned guykes’ flaremax build with sids etc. Surely the 9a is more like the jeht in cotic’s line up?
But don’t let me stop you buying one!
Cortex is a good shout for a bike with very different geometry and intended use. Won’t be that much lighter in the end though, if that’s what op is worried about? Large frame listed as 3.05kg
You mentioned guykes’ flaremax build with sids etc. Surely the 9a is more like the jeht in cotic’s line up?
Flaremax is 125mm travel, aether 9 is 130mm so not much in it, I'd wager the cotic frame is slightly heavier although not by a lot perhaps.
You say your murmur is 34lbs but have you actually weighed it?
Not really no it's a guess based on other bikes before it which were in the 30-32lbs range. The starling is heavier but it's got a fox 36, coil shock, wide rims, big tyres etc. I'm not looking at replacing that bike but replacing the burly hard tail I also own with something lighter and better suited to easier rides.
I have looked 2nd hand but not much is jumping out at me so I'm looking for new frames which don't cost daft money.
Flaremax is 125mm travel, aether 9 is 130mm so not much in it,
Hmm fair point. It’s the putting sids on it that makes it seem shorter travel!
A set of 120mm sids saves you what 350g over pikes? 500g over my 34s. But what would that do to the geometry on the bird? Even the cortex is designed around a longer fork, and is steeper/shorter to start with.
A big travel steel full suss bike with 36’s / coil shock / big tough wheels and heavy casing tyres might well be heavier than you think it is. Would be interesting to test that out by weighing it.
I can't see a murmur weighing that little tbh.
My 9c with 36/x2, zee brakes, Gx Transmission and Flow/Minion wheels is 33.5lbs.
I thought the Aether 9 Carbon frame was about 600g lighter than the Aether 9 Alloy frame?
I asked when I buying my 9C and was quoted this by Dan from Bird when I spoke to him.
Odd that it turned out to be <100g?
I went for the C as at the time the A wasn't out, not for the weight saving.
Using the old weighing myself then weighing myself carrying bike the Murmur weighs closer to 16kg. That's with a DD Aggressor on the bike, that has a hole in it so needs a tube so that's not ideal. I also have a fox 36 on there that replaced a Pike so there is weight saving to be had.
I would not be setting up/building up another bike like this, it would be a much lighter less burly build.
The obvious answer is an Aether7.... Especially a lightly used one...
Throw me £2250 and i can find you one.
Yaris (2021 damper), DPX2 shock, 11sp... etc.
Weighed the 9C today:
9C Medium
Pike Ultimate RC2
Full SLX
Hope Pro 4’s with XM481
Deluxe Ultimate
Unite Renegade and the rest Bird kit inc. peadals
Hutchinson Griffus and Vittoria Agarro
14.6k5g
On my cheapo mountain warehouse luggage scales my medium 9c comes in at 14.58kg.
It’s a lightish build:
Pike ultimate 150mm
Deluxe select+
XT drivetrain
Deore 4-pots + 203/180 RT66 rotors
160mm BY dropper + bird’s standard fabric saddle
Raceface turbine stem & next R 35 bars
XMC 1501 wheels
2.4 Dissector & 2.5 DHF
Hope F20 pedals
Mudhugger Evo front + FRX back + Invisiframe + bottlecage + driveside SS protection.
It was about 13.85kg when I’d just got it back from the invisiframer, before pedals, mudguards and the rest.
Definitely no featherweight, but not a lump either and it feels nicely stiff/burly.
Going by Ben or Dan’s “3060g and up” comment somewhere, that’d make the 9a only 280g heavier. Pretty small difference, but bird’s al frames seem particularly light while the 9c is probably average.
Mine was 16.5kg* medium as collected (with sealant, without pedals). Pike Ultimate, Deluxe Ultimate, Deore, XM481/Pro4, bash guard, DHR2/Dissector, alloy bar.
I think that figure may well be out because a) it’s 2.7kg more than the sum of the published weights of all its components, b) it’s 1kg+ more than the above posters, c) BikeRadar had a higher spec one down to 14.8kg without pedals (that’s 1.7kg lighter).
Re-weighted now using luggage scales rather than myself with/without bike on bathroom scales. Comes to 15kg after subtracting weight of pedals and accessories.
why are you subtracting the weight of the pedals ? It's not like you can ride without any.
It’s useful as a comparison to manufacturer weights (assuming they’re honest).
*sorry for taking you seriously if you were just having a laugh 😀
Yes, just a standard way of providing it for ease of comparison with manufacturers and other posters who might be running lighter pedals.
Bird are unusual in shipping bikes with sealant, so I reckon ~120ml*2 ~= 250g off that figure again for comparison with manufacturer weights, so 14.75kg.
My bike on the scales is actually 16.6kg with pedals, f&r mudguards, and other small accessories for packless riding. Add another 1kg for a bottle of water and a spare tube.