If you're into older air head classic Beemers and serious touring, this was (and still is) THE bike to have back in 1979 and the disco duck/leisure suit crazed "70s doldrums decade". Period. I also believe it was the most expensive stock production bike you could buy (mainstream bike market) back then too... even compared to a similar Harley touring set-up.
30 years later, it still is imminently rideable for yeoman day-to-day commutes or extending touring. No problems. No worries. Just rock solid 'classic Beemer' here... thank you very much. No hassle, no muss, no fuss... and -- of course -- no pizazz. Just practical and reliable touring and the best 'road trip' companion you'll ever have. Comfort food and cozy blanket on wheels... :-) Simple and easy. MX free shaft drive, etc, etc. It's truly a 'for forever bike'... timeless and ruggedly dependable. Am I getting through here? Get my drift? :-)
I have multiple bikes, but this one gets ridden most consistently and regularly... without regret, remorse or regard to general riding conditions, parking situations or weather outlook. I refer to it as my "SUV bike". It's fairing is BIG and totally does the job. Too well in the summer... (those 500cc jugs get HOT)... but it DOES have two nice air vents on each side of the fairing that can be positioned as you like. The windscreen is way too tall for me (because very tall in height 1st owner changed it). But both fairing and windscreen are HIGHLY appreciated on cool morning fall and spring commutes in New England -- complete with rain (or snow flakes). That aspect keeps me waffling about changing out that windshield... :-)
The engine is strong, but not very powerful. I know it's only a two-valve pushrod boxer... but is -- after all -- a liter bike. It's a slug compared to a contemporary touring rig... but wow is this bike comfortable, stable and reliable. And the extra 250ccs or so over R75s and R80s helps. Now I'm no mechanic... but it seems like this engine lacks a serious flywheel effect, because when you roll off the throttle, the revs and momentum sure do disappear quick.
But the R100RT is also LIGHT (relatively speaking) compared to those same modern bikes. Sit on an R100RT... then sit on a Kawasaki Concours (any year model) and you'll see what I mean. The R100RT's lighter set-up means it's more fun to drive (for me). It handles well and also can get up and go nicely with some agility. On the highway at speed... it will go happily all day long to the moon and back at 75+ MPH -- whilst delivering impressive 45+ MPG. Engine seems to come alive at 4500 RPM. Tranny is text book BWW -- with five cogs. Shift kit is highly recommended if you don't like 'text book' BMW gear changing 'CLUNK'.
OK. This particular R100RT has admittedly been "set up" with nice aftermarket, subtle and not so subtle improvements. The fairing is massive and somewhat 'dated' and staid. But actually it still looks presentable and 'stylish' (to some, in a stodgy sort of way) by today's standards. Black on black on unfinished aluminum engine/brightwork... with blue pinstriping and gold finished cast wheels gives it a distinctive, 'honest' and conservative look... but also a VERY purposeful look. Decked out with tank bag and BMW hard luggage and rack, it's ready to go ANYWHERE and for a LONGTIME adventure.
The downside? BMW mechanics mostly don't like the RT full fairing set-up because 1) "the fairing gets in the way and 2) RTs are heavier than RSs". Some even comment that "RTs are old guy bikes". Engine was dated even back in 79. Power output is modest for a 1000cc block, and you feel power pulses from 'big pistons' until 3K RPM or above. But considering the thin/narrow stock rubber in front and in back, you'll probably just want to lug it unhurriedly. If you come across an early R100RT, consider a dual plug mod as it definitely helps the bike idle smoother/lower and respond better. And check to see if alternator has been serviced/replaced as well as any recent tranny work. Head bearings are also prone to loosening up... or so I'm told (and am experiencing now). Other than that, do a compression 'smoke & sniff test' and then buy and enjoy! For miles and years... This IS a classic Beemer air head after all!