This is from the site Bring a Trailer (https://bringatrailer.com/) ...
This 1975 BMW R90/6 is believed to have spent its life in Colorado prior to the seller’s recent acquisition. The bike is powered by an 898cc air-cooled opposed-twin with a 5-speed transmission, and recent work included a valve adjustment, a carburetor rebuild, and a cylinder head re-torque. The lubricants were also changed, and accessories include Krauser hard cases and aftermarket heated grips. This R90/6 is offered at no reserve with the factory tool kit, owner’s manual, and a clean South Carolina title in the seller’s name.
The bike is finished in traditional black with white pin-striping. Features include a 4.75 gallon tank and an optional tail rack with bag mounts. The seat was re-covered by a previous owner, and the seller replaced the battery with an Odyssey gel cell. Weinmann alloy rims wear Heidenau K60 dual sport tires that are said to have fewer than 1,200 miles.
Instrumentation consists of a 140-mph speedometer and a 9k-rpm tachometer. A factory steering damper is provided, and aftermarket heated grips have been added. 38k miles are currently shown on the 5-digit odometer.
The 898cc opposed-twin was factory-rated at 60 horsepower and features dual 32mm Bing carburetors. Power is transferred to the rear wheel via a 5-speed transmission with shaft drive. When purchased, the seller rebuilt and balanced the carburetors, adjusted the valves, and re-torqued the cylinder heads to factory specifications. The engine, transmission, driveshaft, and final drive lubricants were also changed. No service records are available.
Accessories include Krauser hard cases with mounts, and a Denfeld tail rack. Walk around, cold start, and riding videos are provided below.