BLK stands for Benzin (petrol) - Leicht (light) - Klein (handy, compact).

MANUFACTURED BY: STIHL ANDREAS MASCHINENFABRIK STUTTGART, GERMANY SERIES OR ASSEMBLY NUMBER: YEAR INTRODUCED: 1954 YEAR DISCONTINUED: 1973 ENGINE DISPLACEMENT: 98 ccm (6.0 cu. in.) NUMBER OF CYLINDERS: 1 CYLINDER BORE: 54mm (2.16 in.) PISTON STROKE: 46mm (1.8 in.) CYLINDER TYPE: Aluminum with chrome plated bore INTAKE METHOD: Reed valve MANUFACTURER ADVERTISED H.P.: 3.5 WEIGHT : 11kg (24.2 lbs.) OPERATOR CONFIGURATION: One Man operation HANDLEBAR SYSTEM: Rigid CHAIN BRAKE: none CLUTCH: Centrifugal DRIVE TYPE: Bevel gear transmission CONSTRUCTION: Die cast magnesium MAGNETO TYPE: Bosch MZ/UP 1/115/2 CARBURETOR: Tillotson HL-36A (early models used Bing) MAJOR REPAIR KIT: na MINOR REPAIR KIT: DG-1HL AIR FILTER SYSTEM: STARTER TYPE: Automatic rewind OIL PUMP: Automatic, worm gear driven OPERATING RPM: 5,500 produced chain speed of 11m/sec IGNITION TIMING: 3.0mm before TDC BREAKER POINT SETTING: 0.4mm (0.016 in.) FLYWHEEL/COIL AIR GAP: SPARK PLUG TYPE: Bosch W 225 T 7 SPARK PLUG GAP: 0.51mm (0.020 in.) CRANKSHAFT MAIN BEARINGS: 4 ball type FUEL TANK CAPACITY: FUEL OIL RATIO: 25:1 for first 100 hours, 30:1 thereafter RECOMMENDED FUEL OCTANE: Regular MIX OIL SPECIFICATION: Castrol 2-stroke SAE 40 CHAIN PITCH: 1/2 in. CHAIN TYPE: Chipper BAR MOUNT PATTERN: SHORTEST GUIDE BAR SUPPLIED: 30cm (12 in.) LONGEST GUIDE BAR SUPPLIED: 61cm (24 in.) COLOUR SCHEME: Red enamel