This is from the site Bring a Trailer (https://bringatrailer.com/) ...
This 1976 BMW R90/6 was purchased by the seller 9 months ago and is powered by a 898cc boxer twin with a 5-speed transmission. Recently refurbished with fresh paint, tires, handlebars, fork boots, and a new battery. The engine was completely disassembled and refreshed with new seals, rebuilt carburetors, a valve adjustment and re-torquing of the cylinder heads. Currently showing 26K miles, the seller has added 400 miles over the last 9 months. This R90/6 is offered at no reserve with a factory tool kit, and a clean South Carolina Title in the seller’s name.
Re-finished in the correct Glasurit black with hand applied pinstriping, the previous owner installed a German made reproduction seat, and the seller has added new fork boots, a stainless steel brake line, gel cell battery, and a neutral indicator switch. The front turn signals have been removed, and the seller notes staining on left muffler and some discoloration to the header pipes. Alloy wire-spoke wheels wear new Avon tires.
A factory steering damper is fitted, and new 22mm German made handlebars feature fresh Magura grips. The instrument cluster contains a 140MPH speedometer and a tachometer with a 7K redline. 26K miles are currently showing.
The 898cc air-cooled boxer twin is fed by dual Bing carburetors and produces 60 horsepower in stock form. A 5-speed transmission transfers power to the rear wheel via shaft drive. The engine was completely disassembled and all seals replaced including the head gasket, valve cover gaskets, rear main seal, push-rod tube seals, cylinder base o rings, and flywheel nose O ring. The carburetors were also rebuilt, valves adjusted, cylinder heads re-torqued, and drive shaft bolts replaced. The clutch disc was inspected and cleaned as only minor wear was found.
The factory supplied toolkit is included but no service records are available as the seller and previous owners have performed much of the work personally. A cold start, walk around, and riding video can be seen below.