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Am descoperit ieri, (rasfoind site-ul canadian Pinkbike - pe care cred multi il urmariti), o noua inovatie (eu personal nu am mai vazut - poate mai stiti voi) in domeniul transmisiilor la biciclete, si anume trecerea de pe transmisia mecanica pe cea hidraulica...mi s-a parut interesanta ideea desi cam scumpa evident . Transmisie bazata pe servomecanisme am vazut, insa hidraulica nu...din pacate nu am gasit text decat in limba engleza. Sper sa va placa! [i]"Acros' A-GE is an innovative hydraulic derailleur system with a single-paddle shift lever that weighs less than XTR and adapts to 8, 9, and 10-speed cassettes. 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. The Acros front derailleur: note how compact the hydraulic mechanism is barely the size of the adjusting screws on a conventional changer 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. 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 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) "[/i] SURSA: http://www.pinkbike.com/news/Pinkbike-First-Look-Acros-AEG-11-MT-Hydraulic-Shifting.html

Cu tot respectul, cred ca toata lumea de aici verifica zilnic Pinkbike, doar ca putini stau sa si citeasca ce e pe acolo. Interesant, fara doar si poate, dar noi de abia suntem in perioada in care incepe sa se democratizeze calitatea in privinta schimbatoarelor conventionale cu cablu. Idei inovatoare au mai existat: vezi Shimano Airlines, vezi G-Boxx, vezi Rohloff pana la urma, dar inca nu s-a impus nici una. Industria de profil inca este dependenta de comercializarea consumabilelor si nu are nici un fel de interes in a produce ceva atat de fiabil incat schimbul de piese sa devina incetul cu incetul istorie. Asta in general vorbind. Patentul cumparat de Acros e interesant, dar tind sa cred ca la nivel inalt va fi folosit doar de anumiti rideri care nu au afilieri cu SRAM sau cu Shimano, adica undeva in afara top 20, in prima vaza. Traim vremuri interesante, fara doar si poate! Desi si asta e un truism... ;) Personal as vrea sa se intoarca in lumea mountainbiking-ului la modul serios companii precum Campagnolo (nu stiu cati dintre voi au auzit de Euclid sau de Record OR) sau Suntour (XC Pro, anyone), care la vremea lor erau legendare. Dar alea erau vremuri cand fiabilitatea era altfel privita, adica nu prin spectrul consumist de astazi. We'll see! Ah, da! Campa pot sa-si bage in dos toata gama pe 11 randuri! Cred ca si cu 10 am sarit deja un pic peste cal... Mx

chiar zilele astea discutam cu un coleg la facultate sa facem un schimbator hidraulic la bicicleta. mah greu nu poate fi. niste pistonase la schimbator, un rezervor mic pe shifter etc.. dar care i-o fi rostu zau? din greutate nu ai cum sa scazi pt ca un cablu si camasa de schimbator (mai subtiri ca si la frana) cred ca sunt mai usoare decat acelasi sistem dar hidraulic. singura utilitate ar fi daca acel schimbator (spate) ar avea arcuri foarte foarte tari...atat de tari incat sa nu poti clinti maneta cu cablu ci doar printr-un sistem hidraulic.. si ar mai fi un dezavantaj.. care mi se pare foarte mare.. ca si la frane va prinde aer, uleiul se va degrada va fi nevoie de aerisire.. si nu va mai fi precis deloc, chestie care la sistemul pe cablu se poate regla in mers printr-un singur surub pe maneta. eu unu nu-i vad rostu. o fi doar asa sa ia ochii unora PS: eu vroiam sa fac pt licenta o frana hidraulica wireless (fara camasi/furtune etc) ca sa nu se mai dea lumea brakeless dar am renuntat la idee pt ca nu e fiabila si te lasa cand ti lumea mai draga, dar cu componente scumpe nici o problema.. doar banii sunt prob. eh.. vorba lu Mx, traim vremuri interesante :)

foarte tare dar nu am vazut in romania, in al doilea rand eu unul ma consider sarac deci cam cat costa una bucata de spate (un schimbator cu tot cu maneta conducta si aerisite, desigur)

Eu aştept varianta electro-hidraulică :D Edit: UItasem! Neapărat să fie wireless şi conectată permanent pe facebook :))

Foarte interesanta asta,eu personal nu am mai vazut transmisia la bicicleta sa fie hidraulica dar cum spuneai si alti baieti mai sus,scump si de ce? ca pana la urma? nu e ca la o frana sa maresti o putere de...ceva...eu zic ca inca vom mai ramane suficient timp la cele clasice...pe cablu.

Dumitru Bogdan (Bob) Rosu
foarte tare dar nu am vazut in romania, in al doilea rand eu unul ma consider sarac deci cam cat costa una bucata de spate (un schimbator cu tot cu maneta conducta si aerisite, desigur)

Andrei Christian
la ce bun? in afara de faptul ca schimba milimetric, la un crash ai pus-o daca a fost atins, mai multe cabluri, greutatea e relativ aceeasi, dar dai de 3 ori mai multi bani pe ceva ce are o rezistenta materiala mai slaba

Andrei Budan
Foarte interesanta asta,eu personal nu am mai vazut transmisia la bicicleta sa fie hidraulica dar cum spuneai si alti baieti mai sus,scump si de ce? ca pana la urma? nu e ca la o frana sa maresti o putere de...ceva...eu zic ca inca vom mai ramane suficient timp la cele clasice...pe cablu.

Bag de seama ca voua de regula nu prea va place cititul, din moment ce postati orbeste asa, nu? Nu de alta, dar daca v-ati ostenit putin ochisorii, ati fi inteles si care sunt avantajele si de ce fiabilitatea sistemului este un atu. @ Dumitru: greu cu semnele alea de punctuatie, nu? Adica, la naiba, tu sa intelegi ce ai scris, ca restul nu conteaza... ;) @ Mladen: http://www.pidjin.net/2010/05/26/like-guns/ Deci: CITITI (stiu ca e greu si ca nu e asa de cool ca si "manualul Marzocchi, LOL frate!" ) si de abia APOI scrieti pe forum. Ocazional va mai puteti folosi si celulele cenusii, if any. Mx

Mladen Braşovan
Eu aştept varianta electro-hidraulică :D Edit: UItasem! Neapărat să fie wireless şi conectată permanent pe facebook :))

de exemplu: Shimano's Dura-Ace Di2 electronic gears

@Maxi, =)) @Barbat Coriolan Emmanuel, ştiu de Di2, dar ăla-i doar electronic. :) Să nu fiu înţeles greşit, mi se pare interesantă ideea de a avea schimbătoarele acţionate hidraulic, dar ţinând cont că la frânele hidraulice le-a trebuit vreo 10 ani până au ajuns să aibă o calitate decentă la un preţ rezonabil nu mă aştept să am în curând pe bicicletă asemenea schimbătoare. Iar în timpul ăsta cine ştie ce o să mai apară... poate suspensii cu microprocesoare care se ajustează automat în funcţie de teren... Aţi mai auzit mai recent ceva despre Simon ăla stângaci?

Mladen Braşovan
Să nu fiu înţeles greşit, mi se pare interesantă ideea de a avea schimbătoarele acţionate hidraulic, dar ţinând cont că la frânele hidraulice le-a trebuit vreo 10 ani până au ajuns să aibă o calitate decentă la un preţ rezonabil nu mă aştept să am în curând pe bicicletă asemenea schimbătoare. Iar în timpul ăsta cine ştie ce o să mai apară... poate suspensii cu microprocesoare care se ajustează automat în funcţie de teren... Aţi mai auzit mai recent ceva despre Simon ăla stângaci?

Hehe, un vot si de la mine. Daca industria tot ar fi atat de chitita pe evolutie si fiabilitate, am avea cu totii biciclete cu sisteme de schimbare a vitezelor etansate si insensibile la intemperii. Lumea in care traim insa este una "trial and error" in care din pacate consumatorul de rand este sobolan de laborator pentru mai micii sau mai marii producatori. Cu alte cuvinte, pentru proprii bani ai "privilegiul" de a livra feedback celor care fac profit pe seama ta. Ah, ca sa nu uit de faptul ca cel mai mare producator de biciclete din lume INCA nu e in stare sa furnizeze o bicicleta gravitationala cu o geometrie in pas cu timpurile. Deci, cat de greu poate fi??? @ Mladen: Lasa-l pe Simon, ca cel putin pentru clientela snoaba Cannondale ala era un lucru venit in intampinarea nevoilor lor de fucking tech weenies, dar sa (nu) ne aducem aminte de anul de gratie 1998 si de extraordinarele "Smart Shock"-uri montate in gama K2 pe Noleen-uri altfel respectabile? Pana la urma K2 a dat-o de gard cu Proflex, i-au ucis stupid de rapid si lumea a uitat cam la fel de repede ca team-ul Klein din vremurile lui de glorie (Rishi Grewal anyone?) folosea furci Girvin... Cum, Klein? Care Klein, frate, gen, ca daca nu e dartmuor d-ala colorat si nu are sa pivotala nu e cool astazi! ;) @ Felix: Nu sunt sigur ca oamenii catre care dai link nu sunt si cei care au patentat sistemul hidraulic de care se foloseste Acros, fiindca din textul de pe Pinky rezulta ca inventia ar fi fost prezentata la Eurobike acum cativa ani. Pe de alta parte, cine mai stie de Mavic si de Mektronic si, daca tot stie, cu ce le e de folos celor de la Mavic treaba asta? :)) Inca una pentru voi: http://www.youtube.com/watch?v=jCDSZr2zzws ;) Mx