Shimano Alfine Elf-Gang-Naben: Unterschied zwischen den Versionen

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===Bekannte Probleme===
===Bekannte Probleme===


The cable shift control is very sensitive to variations in build tolerance and adjustment. The reason for this is that the cassette joint may only rotate about 135 degrees total, i.e. about 15 degrees per shift, tops. (This limitation occurs because the right-hand hub cone is supported on two prongs, leaving gaps that the selector mechanism pokes though) This makes building the hub accurately very difficult for Shimano and also makes it sensitive to the exact external setting when in use. Unfortunately, with new hubs, the cable usually settles and this throws the external adjustment off; worse still, the build tolerances are such that the 'correct adjustment' (dots lined up in gear 6: http://www.sheldonbrown.com/nexus-mech.html) is not always the 'optimum adjustment'. 'Rofan' (see Alfine 11 reliability thread) has reported that the shift control sleeve inside the hub is lighter built and longer than the equivalent eight-speed versions and this presumably makes it more likely to give trouble through wear or high shift load.
Die Schalthebel sind sehr sensibel gegnüber Variationen in der Aufbautoleranz und Einstellungen. Der Grund dafür ist der Schaltarm, der sich nur maximal 135° bewegen lässt (d.h. 15° pro Schaltvorgang), anschlagen kann. Diese Limitierung begrpndet sich durch den rechtsliegenden Konus, der von zwei Zinken gestützt wird, durch deren Lücke der Auswahlmechanismus hervorlugt. Dadurch wird der Bau der Nabe sehr schwierig für Shimano und die Nabe wird sehr sensibel gegnüber der exakten Einstellung im täglichen Einsatz. Unglücklicherweise setzt sich bei neuen Naben der Schaltzug etwas und die Zugeinstellung wird ungenau: Umso schlimmer sorgen Fabriktoleranzen dafür, dass die "korrekte Einstellung" (Punkte im sechsten Gang ausrichten - siehe auch im Artikel [[Technische Informationen zu Nexus und Alfine Drei-, Vier-, Sieben-, Acht- und Elfgangnaben]]) nicht immer die optimale Einstellung darstellt. Der Benutzer Rofan (im oben erwähnten Thread das CTC Forums) berichtet, dass die Verbindungsmuffe für die Schaltungsansteuerung leichter und länger gebaut ist als ihr Äquivalent in der Achtgang-Nabe. Das führt unter Umständen zu mehr Problemen durch Verschleiß oder durch hohe Schaltkräfte.
 


The helical stage 1 gears were presumably added at a late stage (the EV tech doc shows straight-cut gears), I suppose to make the hub nice and quiet. However this generates an axial thrust load which can cause problems with retention of sun gear 1 on the axle (as jb has described in the reliability thread). Arguably, whoever designed the gear train screwed up here, in that when you pedal hard, the sun pinion S1 is forced rightwards against the retaining clip, rather than leftwards against a fixed shoulder. Maybe there is a good reason for this, but if the helical gear had been cut the other way (or left straight-cut), this fault might not occur in the same way or perhaps at all. The problem is especially likely if you routinely pedal hard in gears 1-6.
The helical stage 1 gears were presumably added at a late stage (the EV tech doc shows straight-cut gears), I suppose to make the hub nice and quiet. However this generates an axial thrust load which can cause problems with retention of sun gear 1 on the axle (as jb has described in the reliability thread). Arguably, whoever designed the gear train screwed up here, in that when you pedal hard, the sun pinion S1 is forced rightwards against the retaining clip, rather than leftwards against a fixed shoulder. Maybe there is a good reason for this, but if the helical gear had been cut the other way (or left straight-cut), this fault might not occur in the same way or perhaps at all. The problem is especially likely if you routinely pedal hard in gears 1-6.
Abgerufen von „https://wikipedalia.com/index.php/Shimano_Alfine_Elf-Gang-Naben“