Abgeschickt von Christian L. am 23 September, 2002 um 18:04:27:
Antwort auf: Getriebe, why pitting on gearwheel. von Sven Erik Tiberg am 20 September, 2002 um 23:00:23:
Hello Sven Erik.
I'm not at all a gearbox specialist, just another victim of BMW poor gearbox and drive train design.
Riding a '91 GS/PD who needed two rebearing of the gearbox and one new drive shaft in a 120kkm lapse.
But I'm not familiar with older airheads, I just can give you some general information who might help you.
a) pitting on 5th gearwheel:
until 1984, the 5th gearwheel (and of course its counterpart) had 15 degrees inclination. From 1984 on, BMW changed
to the longer lasting and more reliable 17.5 degrees inclination.
Please go to (http://www.hw-bochum.de/download/99ER.PDF) where you can find information about remanishing pre '84 gearboxes
to 17.5 degree inclination. The given URL is part of Huschke&Wirth website (german language only/ it's a PDF, you'll need Acrobat reader).
H&W are specialist in mechanical work on airhead engines and gearboxes and they have a very good reputation. They are in Bochum.
I head my heads remade by them and the work looks very good (will be in operation hopefully on saturday 28 September).
b) cluth slipping:
did you think about replacing the rear bearing (crankshaft-cluth)?
Mine one was slowly starting to leak at 110kkm.
PS: never saw any pitting on my gearwheels!
They still are in perfect condition, the flanks look like chrome plated.