Review -

Exclusive First Ride – The New Bird Aeris 145

UK company, Bird Cycleworks will soon be releasing this radical looking Bird Aeris 145 into their range, boasting some major changes from their 2016 Aeris. We have been lucky enough to swing a leg over this 150/160 m (front) 145 mm (rear) travel bike for the last month to see what it was all about.

With Bird now coming into their fourth year of production, their bikes are designed from the ground up in the UK and aimed at the enduro market, targeted at serious trail smashers and racers alike. Looking at the new Aeris, it’s clear that Bird are not afraid to stick their neck out into the “real” long category, with this large frame coming in with a huge reach of 506 mm.

Bird Aeris 145 | 150/160 mm (front) 145 mm (rear) | 13.58 kg | € 4,283 

Bird deal direct, and from the start it’s a very personal experience when selecting your build, colour and spec of choice, with plenty on offer. We were indeed offered choices of bar length and rise, grip thickness and which Maxxis tyres to use prior to the arrival of this bike; a nice touch! It would seem that UK riders are very particular about the builds and specs of their bikes, so Bird have addressed this from the start with so many choices.

Changes to the new Bird Aeris 145

Differences to the previous 2016 Aeris 140 models include:

  • 145 mm rear travel, 150/160 mm front
  • All new 6066 tube set, designed to give best stiffness to weight ratio
  • New self-locking mini-collet axle system
  • One-piece hollow section yoke
  • 148 mm boost rear end for maximum tyre clearance and stiffness
  • One piece brake/axle assembly for maximum precision and minimum squeal
  • Metric shock sizing
  • Double bearing shock mount, to give smoothest shock movement
  • One by specific rear end for maximum stiffness
  • ISCG05 mount
  • Bottle cage mounts

Specification of the new Bird Aeris 145

The large model we tested is the “all singing, all dancing” top of the range SRAM Eagle build, coming in at € 4283 (£ 3700) but they also offer another five build options with different price points and a frame-only option available from € 1041 (£ 900) This bike comes equipped with SRAM’s new Eagle 12 speed drivetrain, The latest RockShox Deluxe or Super Deluxe Metric RC3 DebonAir 230 mm x 65 mm rear shock and ours came kitted with the RockShox Lyric RCT3 160 mm fork.

Rock Shox new 2017 metric Super Deluxe shock smoothing out every bump with ease.
145 mm of travel on the rear, it feels like so much more!
Fitted with the wide 30 mm DT Swiss M502 rims, lateral tyre support was fantastic.
We always love the class-leading comfort of the Fabric Scoop saddle.

SRAM also take care of the braking with their reliable Guide RS brakes and 180 mm (front) 160 mm (rear) rotors. Of course the rear of the bike will be Boost 148 x 12 mm axle and ours came with the very nice looking Unite Components chain guide. We have some carbon bling on this bike too, with use of the SRAM XO cranks and Race Face’s SIXc bars.

This build came equipped with SRAM’s Eagle rear cassette.
Unite Components new UK chainguide keeping the chain on the Eagle chainring.
For simplicity of maintenance, we commend Bird for external cable routing.

The height of the very comfortable Fabric Scoop TI railed saddle is handled by the popular RockShox Reverb Stealth 150 mm post. In the wheel department things are looking tough and reliable, Hope’s Pro4 hubs are laced to DT Swiss’s nice wide 30 mm (inner width) M502 alloy rims. Of course with this bike being long in the reach, then the Race Face Turbine stem has to be 35mm long, or should we say short!

With such a long reach of 506 mm, a short 35 mm stem is essential, quality Race Face components taking care of this job.

Geometry of the new Bird Cycleworks Aeris 145

Size S M ML L XL
Seat tube 380 mm 410 mm 440 mm 470 mm 500 mm
Top tube 580 mm 605 mm 630 mm 655 mm 680 mm
Head tube 110 mm 110 mm 120 mm 120 mm 130 mm
Head angle 65 ° 65 ° 65 ° 65 ° 65 °
Chainstay 435 mm 435 mm 435 mm 435 mm 435 mm
BB Drop 10 mm 10 mm 10 mm 10 mm 10 mm
Wheelbase 1178 mm 1203 mm 1230 mm 1255 mm 1282 mm
Reach 433 mm 458 mm 481 mm 506 mm 528 mm
Stack 589 mm 589 mm 599 mm 599 mm 608 mm

Feel of the new Aeris 145

With our tester being 178 cm tall, we went for the large, with 70 psi in the RockShox Lyric RC3 fork and 145 psi in the RockShox Super Deluxe RC3 Debonair shock. Sat upon the Aeris it feels terrifically roomy with the long reach, but not over the top on length, this is largely due to the steep and efficient 75.5° seat tube angle.

Climbing on the new Bird Aeris 145

This is a long bike with it’s 506 mm reach, but with the steep seat tube it climbs amazingly well, keeping the rider’s weight central between the two wheels, thus avoiding the bike having any want to wheelie on the steeper terrain. Flick the RockShox Super Deluxe Debonair’s lever to climb and any excessive bobbing is instantly removed, whether climbing or sat. With a weight of 13.58 kg (29.15 lbs) on our scales, this bike is easily capable of busting out day-long climbs befitted to it’s mega-light carbon higher priced competition.

With a nice steep seat angle of 75.5° this bike climbs with incredible ease.

Descending on the new Bird Cycleworks Aeris 145

Flick switches to fully open, assume the downward attack position and let this bike loose on the gnarliest of terrain and you are gifted with such an aggressive feeling bike, way beyond it’s description of a 145 mm travel machine. The long reach and aggressive 65° head angle mixed with the 435 mm short chainstays makes for an incredibly stable yet playful ride indeed. The small bump sensitivity of the latest generation 2017 RockShox suspension is far superior than it’s predecessors, offering a plush confidence inspiring ride.

The Aeris 145 rails turns so well, begging for more speed!

On full tilt and fired into corners, this Aeris just begs to be ridden harder and faster, making the rider feel like they are out for that EWS win! Our tester found heaps of joy nailing the roughest of sections and firing off large lips on this bike, admitting he was very surprised at its ability in all situations. This is one fast aggressive bike on the downhills that leaves a true smile on the rider’s face. The Maxxis Shorty front and Maxxis Minion DHR for the rear hooked up well in the snotty riding spots of the UK, offering heaps of grip and bite with the 1255 mm wheelbase.

Roots, rocks and rough stuff is what we think this bike is best at!

Improvements we’d like on the new Bird Aeris 145

We usually find something we would like to change when testing bikes, we have thought long and hard over the past month about whether anything is letting this bike down and to be honest haven’t come up with much! With our test rider being a rider with long legs, he could maybe have prefered a 170 mm dropper post if there was a preference, but that’s it. Some folk may not be too keen on the arrangement of the outer routed cables, but as riders who like to do our own bike mechanics we feel this is far more practical (if not quite as neat) as fully internal routing.

Bottom Line of the new Bird Aeris 145

Many may not be into the whole Brexit thing, but one thing it is starting to change in the UK is where folk are thinking of buying from. With no real minus points from us on this bike it is quite a rarity, it is on-point when it comes to pricing, looks fantastic, mixes standard aggressive geometry with forward thinking length and seat angle and rides all terrain just so well. For someone who either wants an everyday trail smasher, occasional or obsessed enduro racer we feel this bike really is a perfect choice.

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Two words for the new Bird Aeris 145 “confidence inspiring”.
We feel this bike will be a very popular choice amongst UK grassroots riders and racers alike.