1989 BMW R 80GS

Make Model	BMW R 80GS
Year	1989
Engine	Four stroke, two cylinder horizontally opposed Boxer, pushrod operated 2 valves per cylinder
Capacity	797.5 cc / 48.7 cu in.
Bore x Stroke	84.8 x 70.6 mm
Cooling System	Air cooled
Lubrication	Wet sump
Compression Ratio	8.2:1
Induction	2 x Bing constant depression carburetors
Ignition	Battery ignition
Alternator	Bosch 12 V/280 W
Spark Plug	Bosch W 7 D / Beru14-7DU / Champion N9YC
Starting	Electric
Max Power	37 kW / 50 hp @ 6500 rpm
Max Torque	61 Nm / 6.2 kgf-m / 44 ft lb @ 5000 rpm
Clutch	Dry single plate, with diaphragm spring
Transmission	5 Speed
Final Drive	Shaft
Gear Ratio	1st 4.40 / 2nd 2.86 / 3rd 2.07 / 4th 1.67 / 5th 1.50:1
Rear Wheel Ratio	1:3.20
Frame	Double loop tubular frame with bolt on rear section
Front Suspension	∅40mm Marzocchi telescopic hydraulic forks.
Front Wheel Travel	225 mm / 8.8 in
Rear Suspension	BMW Paralever swinging arm
Rear Wheel Travel	180 mm / 7.0 in
Front Brakes	Single ∅285mm disc
Rear Brakes	∅200mm Drum
Front Tyre	90/90 x 21S
Rear Tyre	13/80 x 17S
Dimensions	Length 2290 mm / 90.1 in Width 1000 mm / 39.3 in Height 1165 mm / 45.8 in
Wheelbase	1514 mm / 59.6 in
Ground Clearance	200 mm / 7.87 in
Seat Height	850 mm / 33.5 in
Wet Weight	210 kg / 462 lbs
Fuel Capacity	24 L / 6.3 US gal
Average Consumption	6.3 L/100 km 15.8 km/l / 37 US mpg
Braking 60 km/h - 0	16.0 m / 52.5 ft
Braking 100 km/h - 0	46.3 m / 152 ft
Standing ¼ Mile	13.7 sec / 149.6 km/h / 93 mph
Top Speed	170.4 km/h / 106 mph
Road Test	Bike Magazine Group Test 1992

An upgraded bike arrives with a new rear suspension, the paralever in place of the monolever. A change also for the name, the most visible is that the '/' between the G and the S disappears, but also the meaning of the letters changes. Now, the S is for Sport (in place of Strasse, "street" in German).
The monolever, the mono suspension flexible arm contains the drive shaft, but this one is dry
The rear wheel is fixed by 4 lugnuts in place of the previous 3.
The major differences between the two bikes are :
the oil-cooler on the R100GS (strangely placed on the right engine protection bar);
a small windshield on the R100GS;

The engines :
For the R80GS : 798 cm³, 84,8mm x 70,6mm, 50 hp (37 kW DIN) at 6500 rpm, 61 Nm at 3750 rpm, Compression: 8,2:1, 2 Bing carburators 32mm, 5 speeds;
For the R100GS : 980 cm³, 94mm x 70,6mm, 60 hp (44 kW DIN) at 6500 rpm, 76 Nm at 3750 rpm, Compression: 8,5:1, 2 Bing carburators 40mm, 5 speeds.
The differences from the previous generation are :
the rear suspension;
the rear frame with small rack;
the fork (40mm Marzocchi in place of 36mm BMW);
the front brake (not better, unfortunately);
the centerstand design (pedals curved out);
the wheels (rear 17'' diameter vs: 18'') with rim-mounted spokes (to permit a tubeless tire);
the small external tachometer and clock on the outer sides of the plastic dashboard (maybe an option for the R80GS);
the tank with two petcocks (24 lit./5,8 gal. vs: 19,5 lit./5,1 gal.) and the vent tube goes horizontaly;
the tool box under the seat;
the styling (side panels, rounded tank with knee depressions, the mirror and the seat goes on the tank);
a stainless steel exhaust with a black cover plate (smaller than the R80G/S PD and the R80ST);
the 12v/25Ah battery in place of a 12v/16Ah;
the weight : 210 kg;
no kickstarter (but available as an add-on).
Source micapeak.com