Am heading to 135K on my '96. I've loved having it. Came from a long time on Airheads so learning curve was a cinch.
Bought mine at 66K and things kinda trickled in here and there needing updating/replacement:
Brake master replaced (rebuilt once by PO, once by me. Research this)
Final Drive seal (large) (seal was updated in production, later seal better)
Leaky left head gasket (gaskets upgraded in production, later better)
Worn right throttle body (go used or rebuild)
Ohlins shocks (from PO) both need overhaul, had to find used stockers to keep riding daily-driver GS.
Driveshaft at 116K (front joint got bindy)
Seat vinyl eaten up by UV (eBay for used)
Cam chain tensioner (not a failure, just a nice quiet production upgrade)
Headlight switch melted (circuit is unfused and needs relay. Replaced w/ used until later circuit upgrade)
Headlight H4 female terminal melted (see above)
Hall sensor failed in classic style (but also 6 miles from home on the way back from 2 states away
Steel tank lining coming off in sheets (went with a good plastic '95 tank until steel unit can be cleaned)
All this stuff adds up to some solid $$, but it's just an item or 2 per year in the 6 years i've had it, not all at once. All ops done by me, it's never seen a pro shop. I would tackle major overhaul of every component on the bike, with possible exception of gearbox. And there's so much experience and wisdom here that given enough time, i might even make a go at that.
Been through a pile of tires, brake pads, oil and filters etc.
engine (aside from head gasket and cam tensioner), gearbox, clutch throwout stuff, brain, alternator, fuel pump, ABS, wheel & swingarm bearings, and final drive gears are as-is from assembly line in Berlin.
I like it on ranch roads, logging roads, gravel, etc. Deep sand not so much. It does Urban Warfare commuting and grocery getting par excellence
. They don't tout that much in the promotionals b/c it's not as sexy as Dakar/Globetrotter fantasy-- but the GS as Uber Hooligan bike is one of the strongest suits the GS fills IMO
I like it a ton. I'd buy another