On line OEM parts catalog

[Kjell Lindberg]

RealOEM.com Online BMW Parts Catalog

I could even find some parts for old R60 models

However newer ones like the R80GS Basic have already started to have many obsolete OEM parts.
(According to the lists on the web page)

Thank you Honda for your spare parts policy

//Kjell

[Rubberchicken]

If not their spare parts prices

BMW Boxer Supplies webshop is good for most things airhead.