Maico GM STAR 250 1986, Owner'S Manual

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GM250 and GME250
GM250 GME250
ENGINE
Type 2-stroke liquid cooled
System Reed valve
Displacement 247 cc
Bore/Stroke 67/70
Performance (kW/PS) 36 /49 @8000
Max. Torque 40 @7400
Compression ratio 14.7:1
Combustion space 20.5 ccm
X-distance 0.5 mm
IGNITION
System Motoplat pointless ignition SEM/Motoplat
pointless ignition
Ignition advance 0.4 mm btdc 2.0 mm btdc
Spark plug NGK B9ES (B10ES)
Rotor Inboard rotor External rotor
PISTON DIAMETER LIST
Standard 66.97 EDV-No. 8370
1
st
oversize 67.37 EDV-No. 8373
DRIVE
Clutch 5 sintered, 2 organic outer plates, 6 inner plates
Primary reduction ratio 2.567 (67/26)
1
st
Gear 1.875 (30/16) 2.285 (32/14)
2
nd
Gear 1.555 (28/18) 1.705 (29/17)
3
rd
Gear 1.300 (26/20)
4
th
Gear 1.090 (24/22)
5
th
Gear 0.916 (22/24)
Secondary reduction ratio 4.000 (52/13) 3.250 (52/16)
Chain 5/8” x 1/4” 116 links 114 links
CARBURETTOR
Type Bing 54/380/121 Bing 54/380/121
Main jet 195 135
Needle jet 280-2 278-2
Idle air jet 65 65
Jet needle/position 6D2/M 6D2/M
Air screw opening 0.5 - 1 1
Slide 2103 2103
I. TECHNICAL DATA (continued)
1986 MAICO Owners Manual
www.maicowerk.com
Courtesy of www.franklins.biz