Pinkbike First Look: Acros A-GE Hydraulic Shifting
Acros is an elite German components maker that offers an index-shifting derailleur system actuated by a pair of slim hydraulic lines that reportedly weighs only 426.4 grams ready to rock. Yes; you heard it correctly—front and rear derailleurs, right and left shift levers and all hoses filled with mineral fluid. The Acros A-GE system isn’t a prototype pipe dream either. Acros has 250 sets boxed and ready for sale at a surely-not-for-everyone projected retail price of $2306 US dollars.
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Acros A-GE Hydraulic Shifting Basics
Beautifully machined from aluminum, the Acros A-GE transmission promises to either set a new standard, or hearken to the mid-1990s when a half-dozen North American machine shops took a crack at Shimano with expensive, multi-colored copies of existing gear-changers. Potentially, the Acros A.GE 1.1 hydraulic transmission has some unique features that cannot be attained using cables. Time will tell, but if it operates as advertized, the Acros system may be the first exception to the, nobody-can-beat-Shimano’s derailleur technology rule. Pinkbike grilled Acros about the benefits of its hydraulic shifting system and prepared this special report to introduce the concept.
![photo]()
What is the major benefit that A-GE brings to the table?
Acros says that the primary reason they produced a hydraulic shifting system was that it offered the least amount of friction. The A-GE shifting lever actuates the derailleur with a “UNI-FORCE” two-line, push-pull design that nearly eliminates the need for stiff return springs. Shifting feels light and consistent across the entire range of gears.
Are the shift levers conventional?
No. A-GE Shifters have a single thumb paddle that shifts up or down the gearing range. Pushing the lever upwards shifts to a taller gear and pushing the lever downwards downshifts. One to three shifts can be managed with a single push. Switching the hydraulic lines allows the user to reverse the shifting from “top-normal” to “low-normal” as wished.
Can the shift levers be used with any brake levers?
Yes. Acros’ MY-MOVE lever mounts allow the levers to be positioned in a number of ergonomic locations, and both ahead or behind the brake lever.
How can Acros derailleurs and shifters be lighter than SRAM or Shimano and still be strong?
We will address the durability issue when Pinkbike gives the A-GE a thorough test. Acros states that much of the weight savings are derived from the elimination of steel cables and steel-wrapped cable housing, which add up quickly. In addition, push-pull hydraulics eliminates the need for steel return springs on both derailleurs. Acros makes extensive use of alloy Torx hardware to shave off a few more grams as well.
Will I be stuck buying an Acros-compatible crankset, chain and cassette?
Acros A-GE uses a timing device called a Raster Rod which can be switched out to adapt the derailleur shifting to all conventional eight, nine and ten-speed cassettes and chains.
What happens if I get air in the hydraulic line?
Air must be bled from the system like a hydraulic brake. This is unlikely to happen, however, because Acros hydraulic shifting is a closed system and is not exposed to excessive heat, nor is it required to compensate for pad wear like a hydraulic brake. Should the Acros system be compromised, its front and rear derailleurs can be positioned by hand to adjust for an acceptable gear and will remain there until you get back to the trailhead.
Will it survive a crash?
We have learned that hydraulic brake lines are far tougher than first anticipated—it’s rare that anyone damages one in a crash. Acros’ shift lines are smaller and we assume, more fragile than a brake hose, but it should be noted that a hydraulic hose will still shift properly when badly kinked, as long as fluid can pass through the damaged area. For a downhiller, being able to shift after a crash mangled the derailleur cable could mean a podium finish.
Can I get a short-cage rear derailleur for my DH ride?
The first 250 systems were made with medium cages, but Acros will make long and short-cage versions as well.
![photo]()
Mechanically, are there any compelling reasons to switch from a perfectly great working SRAM X.0 or Shimano XTR to an Acros hydraulic system?
Riders who live in extreme cold have all suffered failures when water freezes inside the housing and the cables simply won’t budge, and a sealed hydraulic system will operate happily in muddy, sloppy conditions that can make shifting cable-actuated systems a wrestling match. The single-paddle shifter could offer an advantage. SRAM experimented with its push-push single-lever road system when it developed XX, but abandoned it because of the excessive lever pressure required to push against the derailleurs return springs. The hydraulic action of Acros A-GE does not require return springs, so it could be an improvement.
Is the Acros A-GE the first hydraulic shifting system?
No, but it may be the first complete hydraulic derailleur transmission. California downhill racer Scott Fyfe designed and marketed a hydraulic shifting system under the S.A.F.E brand in the mid 1990s. The S.A.F.E shifter operated a piston and cylinder that fit into the rear derailleur housing stop and pulled a conventional changer with a short wire link.
Is the Acros the inventor of the system?
NO. We asked Acros' Marius Wrede and he said: "Christoph Muthers invented the system and presented it at the Eurobike 2006. In that moment we saw the potential of the system and that it fits to Acros. We stayed contact ever since and helped in little sourcings. In 2009 Christoph asked us if we are still interested in continuing the project. We did not hesitate and said YES! Christoph is now in our R&D team and we have modified the hydraulic gear to meet industrial standards as well as keeping up with the new “standards” in mountain biking."
What does Pinkbike think about Acros hydraulic shifting?
Anyone who rides hard is going to tear up equipment, and 2300 dollars is a lot of money to spend on shifters and derailleurs that probably will have to be replaced in a few years. That said, racers and anyone who rides in extreme weather or terrain could benefit from a shifting system that has the potential to shrug off nature’s fury or survive a serious crash.
Acros A-GE transmission by the numbers:
Shifter (each): 64.85g
Rear derailleur: 159.84g
Front Derailleur: 79.15g
Hydraulic line (R): 24.26g
Hydraulic line (F): 17.16g
Fluid (R): 9.00g
Fluid (F): 7.25g
Price: $2306 USD (est)
Contact Acros about the availability of the A-GE transmission
Give us your opinion about the future of hydraulic shifting.
The Acros front derailleur: note how compact the hydraulic mechanism is barely the size of the adjusting screws on a conventional changer
Acros A-GE Hydraulic Shifting Basics
Beautifully machined from aluminum, the Acros A-GE transmission promises to either set a new standard, or hearken to the mid-1990s when a half-dozen North American machine shops took a crack at Shimano with expensive, multi-colored copies of existing gear-changers. Potentially, the Acros A.GE 1.1 hydraulic transmission has some unique features that cannot be attained using cables. Time will tell, but if it operates as advertized, the Acros system may be the first exception to the, nobody-can-beat-Shimano’s derailleur technology rule. Pinkbike grilled Acros about the benefits of its hydraulic shifting system and prepared this special report to introduce the concept.
Acros reinvented handlebar shift lever. Pressing the paddle shifter at a slight angle, up or down, determines the direction of the gear change.
What is the major benefit that A-GE brings to the table?
Acros says that the primary reason they produced a hydraulic shifting system was that it offered the least amount of friction. The A-GE shifting lever actuates the derailleur with a “UNI-FORCE” two-line, push-pull design that nearly eliminates the need for stiff return springs. Shifting feels light and consistent across the entire range of gears.
Are the shift levers conventional?
No. A-GE Shifters have a single thumb paddle that shifts up or down the gearing range. Pushing the lever upwards shifts to a taller gear and pushing the lever downwards downshifts. One to three shifts can be managed with a single push. Switching the hydraulic lines allows the user to reverse the shifting from “top-normal” to “low-normal” as wished.
Can the shift levers be used with any brake levers?
Yes. Acros’ MY-MOVE lever mounts allow the levers to be positioned in a number of ergonomic locations, and both ahead or behind the brake lever.
How can Acros derailleurs and shifters be lighter than SRAM or Shimano and still be strong?
We will address the durability issue when Pinkbike gives the A-GE a thorough test. Acros states that much of the weight savings are derived from the elimination of steel cables and steel-wrapped cable housing, which add up quickly. In addition, push-pull hydraulics eliminates the need for steel return springs on both derailleurs. Acros makes extensive use of alloy Torx hardware to shave off a few more grams as well.
Will I be stuck buying an Acros-compatible crankset, chain and cassette?
Acros A-GE uses a timing device called a Raster Rod which can be switched out to adapt the derailleur shifting to all conventional eight, nine and ten-speed cassettes and chains.
What happens if I get air in the hydraulic line?
Air must be bled from the system like a hydraulic brake. This is unlikely to happen, however, because Acros hydraulic shifting is a closed system and is not exposed to excessive heat, nor is it required to compensate for pad wear like a hydraulic brake. Should the Acros system be compromised, its front and rear derailleurs can be positioned by hand to adjust for an acceptable gear and will remain there until you get back to the trailhead.
Will it survive a crash?
We have learned that hydraulic brake lines are far tougher than first anticipated—it’s rare that anyone damages one in a crash. Acros’ shift lines are smaller and we assume, more fragile than a brake hose, but it should be noted that a hydraulic hose will still shift properly when badly kinked, as long as fluid can pass through the damaged area. For a downhiller, being able to shift after a crash mangled the derailleur cable could mean a podium finish.
Can I get a short-cage rear derailleur for my DH ride?
The first 250 systems were made with medium cages, but Acros will make long and short-cage versions as well.
Evidence of intensive machining is obvious on every piece of the Acros rear derailleur this is the medium-cage version
Mechanically, are there any compelling reasons to switch from a perfectly great working SRAM X.0 or Shimano XTR to an Acros hydraulic system?
Riders who live in extreme cold have all suffered failures when water freezes inside the housing and the cables simply won’t budge, and a sealed hydraulic system will operate happily in muddy, sloppy conditions that can make shifting cable-actuated systems a wrestling match. The single-paddle shifter could offer an advantage. SRAM experimented with its push-push single-lever road system when it developed XX, but abandoned it because of the excessive lever pressure required to push against the derailleurs return springs. The hydraulic action of Acros A-GE does not require return springs, so it could be an improvement.
Is the Acros A-GE the first hydraulic shifting system?
No, but it may be the first complete hydraulic derailleur transmission. California downhill racer Scott Fyfe designed and marketed a hydraulic shifting system under the S.A.F.E brand in the mid 1990s. The S.A.F.E shifter operated a piston and cylinder that fit into the rear derailleur housing stop and pulled a conventional changer with a short wire link.
Is the Acros the inventor of the system?
NO. We asked Acros' Marius Wrede and he said: "Christoph Muthers invented the system and presented it at the Eurobike 2006. In that moment we saw the potential of the system and that it fits to Acros. We stayed contact ever since and helped in little sourcings. In 2009 Christoph asked us if we are still interested in continuing the project. We did not hesitate and said YES! Christoph is now in our R&D team and we have modified the hydraulic gear to meet industrial standards as well as keeping up with the new “standards” in mountain biking."
What does Pinkbike think about Acros hydraulic shifting?
Anyone who rides hard is going to tear up equipment, and 2300 dollars is a lot of money to spend on shifters and derailleurs that probably will have to be replaced in a few years. That said, racers and anyone who rides in extreme weather or terrain could benefit from a shifting system that has the potential to shrug off nature’s fury or survive a serious crash.
Acros A-GE transmission by the numbers:
Shifter (each): 64.85g
Rear derailleur: 159.84g
Front Derailleur: 79.15g
Hydraulic line (R): 24.26g
Hydraulic line (F): 17.16g
Fluid (R): 9.00g
Fluid (F): 7.25g
Price: $2306 USD (est)
Contact Acros about the availability of the A-GE transmission
Give us your opinion about the future of hydraulic shifting.
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For those with $2306.
Great Idea but it has massive potential else where.
edit: (sure, you can get a gearbox bike, but its not the accepted norm.)
Currently yes, it's a bit pointless for that kind of price tag but give it time to come down in price I wouldn't be surprised if 10 years on from now hydraulic shifting is standard; similar to v-brakes and hydraulic brakes now.
doesn't sound right does it?
Kids that have no idea how the industry works piss me off.
i think a fair few people would remember airlines
www.5rot.com/schaltwerk.html
If it would look any better, I would still buy XTR
that said last spring I bought a carbon santa cruz with XT, in the fall I upgraded the cranks, bars, seat post. This spring I upgraded wheels... maybe this fall??? and then if i get some nice magura carbon brakes I'll have the sickest bike ever...
OR
I could pay tuition... it is sad bikes cost that much.
Did i mention that the cable system is 75% lighter to (20-25 grams). www.powercordz.com
The important question is: how expensive is the production really? I could imagine that the first "real" series will sell for prices like XTR or XX.
Anyways, congratulations for their engineering ingenuity. Having experienced the superb quality of earlier Acros products, I guess they are here to stay.
Besides that the idea is very good but with too many lines to manage
Dude! There is way not enough ACTIVE Scepticism in our world so back off. Humans evolve buahaha, into sales bullshitters and overweight diabetics buahaha
And what were you getting at with the Hitler reference??? I didn't know Glen Beck was on Pinkbike!
DeeMax Ultimate $2300
Fox40RC2 $1800
My new Acros A-GE shifting: $2306
Cobalt Bolt Cutters: $30
Losing your bike while eating a cheesburger at Mikky D's: Infuriating
That price will keep it off all our "working-man" bikes, for dang sure.
Get it comparable to even XX or XTR, and maybe...
and i would spend the money on it, maybe ... but it would need to come with something like a 10 year warranty for everything
if it breaks ... if i crash and break it ... any thing any thing any thing ... i want to go the next 10 years never having to worry about buying a new shifter or derailleur
lets face it ladies and gents ... this is the way of the future ... no choice about it ...
5 years ago it was 8 speed cassette now 9's and the 10's are being phased in forcing you to get new shifters, chain, cassette, derailleur and 10sp chain rings // not like you can just put the new 10sp sram derailleur on a 9 speed cassette (ive tried with sram X9 10speed on a 9speed cassette - its a no go :-/ )
AND AFTER 90% OF bikes run a 10 speed they have to create the new and improved product so we keep buying new stuff
low and behold ... the new stuff ... at least it looks good
and with prices like that Acros is going to be the ferrari of the bike world
Acros are a high end German manufacturer and the production will not move from in house. Break the set down, there are 248 individual parts at a cost of $2300, that works out at just $9 per part. To machine in house, anodise, laser etch etc etc, its not all that bad. Dont forget about all the small pistons etc that are super expensive to machine.
The whole system is fully rebuildable. Trash a mech and you can completely rebuild it at home. By the time you bought a XX gruppo, trashed 2 mechs, you'll only be a few hundred $ away from this system.
The original concept was realised by Christian Muthers under the 5Rot brand. This never made production due to the development and manufacture costs, not to mention the logistics! Christian now works for Acros as a top designer and sold the designs to them. They had the power and funding to turn 5Rot into a reality. Its taken 5 years of development, even from the point Christian had it to get it to market!
It runs on a fully sealed system which is dead easy to bleed. You simply remove 2 bleed screws from the shifter and push fluid all the way down and round the whole system. It is adjustable both at the mech and shifter if you get issues on the trail, simply by adjusting the piston screws.
Production versions will house the 2 smaller cables into one so you wont end up with more cables than at the moment.
J
Warren
Great Idea but it has massive potential else where.
So why when you have the power of hydraulics continue to use a spring and not a closed system?
Seems a very small step to a long term solution. Cables will be like they are with brakes at some point, but I feel not with this solution.
Cable disk brakes where holding me back. I love my hydros.
My shifter-derailleur combo only holds me back when I don't plan my shift or my hanger is bent. Only having 9 cogs on my cassette doesn't hold me back so I don't need 10. In fact 8 would probably be good enough for me. (Freeride doesn't require a regular cadence.)
If your shifter-derailleur combo is holding you back and it's not just a lack of shifting skill then you need something better. Start saving for the hydro-shifters. The rest of us are probably good for now and will switch when the industry stops making parts for the old style.
most rider ahave fixed derailler problems , on the trails , in races , whit anything to could get their hands on.
shifter , deraillers and cables are changed in parking lots in minutes for a couple of bucks (ok , maybe $50-$75 for rear SLX of X7 that can get you going)
i dont see that hapenning whit these hydrualics , regardless of their price.
that's a major setback.
it's the same whit hydro brakes , i know. but the performance from hydro brakes makes the trouble (when compared to machanical disk brakes) worth it.
i dont see that benefit for running a hydraulic transmission setup.
only time will tell i guess.
Looking forward to test these babies!!!!!
C'mon, today is the 11th April, not the 1st!!!
what are the benifits of hydraulic over cable in a gear system? sure in brakes its pure power but, in gears?
easier up shifts..........
yea thanx, cos my weedy wimpy little thumbs are having soooo much trouble not being strong enough to up'shift against those oh so powerfull return springs..................................(sarcasm btw)
Everyone cries about new and really out there technology at first; and then sooner than later everyone is rocking it. When suspension was first introduced, or when the jump from 8spds to 9 happened, linear pull brakes to disc brakes....wah!!! None of it was initially widely accepted.
hydraulic, electric, pneumatic(shimano airlines!). Same horse different cart. it's still a r. mech waiting to get ripped off the hangar.
And what happens when you stack it 25km into a ride and tear one of your hoses out?? You're f*cked, that what happens. Even the current system can be bodged into a usable gear in an emergency and only costs a few quid to fix.
www.5rot.com/schalthebel.html
An XTR set has an MSRP of over $700. As a brand new technology claiming to be the best, it should cost at least more than $1000 (maybe not $2300, though).
A
for $10,000
dont get me wrong, im impressed! but way out of the average consumers budget
if I won the lottery :p