Modenas Gt128 Manual Book Jun 2026

: Regularly inspect the chain drive, tire pressure, and battery (12 V, 4.5 Ah). Service Intervals

: Community-shared digital copies (PDF or zip) are often found on platforms like or enthusiast Facebook groups Parts Identification Modenas Gt128 Manual Book

I noticed a few people asking about specific maintenance schedules and indicator lights for the GT128 recently. I managed to get a soft copy of the and thought I’d share it here for everyone’s reference. : Regularly inspect the chain drive, tire pressure,

| Parameter | Specification | | :--- | :--- | | | 4-stroke, DOHC, single cylinder | | Displacement | 134.9 cc | | Bore x Stroke | 54.0 x 58.8 mm | | Compression Ratio | 11.0 : 1 | | Fuel System | Keihin CVK 26mm carburetor | | Transmission | 5-speed, constant mesh (1-down, 4-up) | | Final Drive | 15T / 44T chain (#428) | | Front Suspension | 30mm telescopic fork | | Rear Suspension | Uni-Trak monoshock (5-step preload) | | Front Brake | Single 245mm disc (2-piston caliper) | | Rear Brake | 130mm drum | | Fuel Tank Capacity | 4.0 Liters (Reserve: 1.1 Liters) | | Parameter | Specification | | :--- |

Per the manual’s “General Lubrication” chart, apply high-quality grease every 6 months: