I borrowed this, but to paraphrase...
1981:
• Colors: turquoise blue, red, ?
• Dual front disk brakes with ATE calipers.
• Hundreds of small improvements to all BMW boxers, from which the R65 benefitted as well. Major improvements:
[ch9702] Electronic ignition
[ch9702] 40% lighter flywheel (revs & shifts easier)
[ch9702] Nikasil lining in cylinders
[ch9702] Plastic airbox & "pure air" system (allows richening of carburetion while still meeting emissions regulations)
[ch9702] Larger valves (by 2mm each)
[ch9702] Additional crossover pipe in exhaust
[ch9702] Larger oil pan (increases oil capacity by .2 quart)
[ch9702] More cushioning in driveshaft Y throttle cable with splitter instead of two cables. (Many don't consider this an improvement.)
1982:
• R65LS introduced.
• Slight carburetion changes (idle jet & needle position) to all R65s.
• Non-LS R65s all have a single front disk brake, with ATE caliper.
• R65LS gets the dual front disk brakes, with Italian Brembo calipers. (See r65ls.faq)
1983:
• Colors: turquoise, black, ?
• Every year, BMW fiddled with the needle position and idle jet on the carburetors, but these bikes remained basically the same.
1984:
Last year of R65LS and dual-shock R65 model.