Top Performances Maxi Kit Racing Cylinder-piston kitRef : TPF00180A / 1127342

The TOP PERFORMANCE Maxi Racing Cylinder Kit (ref. 9921760) transforms your engine base into an 85 cc race-oriented unit for urban and roadster use. Designed for riders seeking a responsive engine, it combines a special cast iron cylinder "MINACROM" and a high-silicon alloy piston, featuring a racing compression configuration. Ideal for those looking to optimize power delivery and RPM without promising unverified figures.

Attention: can only be mounted with the crankshaft reference 9920410.

Delivery contents:

• 1 cylinder Ø 49.5 mm in special "MINACROM" cast iron
• 1 piston Ø 49.5 high-silicon alloy
• 1 chrome steel piston ring 1 mm
• 1 piston pin Ø 12 x 42 mm
• 1 bearing for pin Ø 12 x 15 x 15 mm
• 2 circlips for piston pin
• 1 combustion chamber and 1 cover
• Several Viton O-rings (various diameters) and 1 O-ring Ø 104.37 x 3.54
• 1 temperature sensor reduction, 1 M14 x 1.25 plug and aluminum gasket
• 1 cylinder base gasket 0.5 mm and 1 exhaust reduction sleeve Ø 28→25 mm

Key features: Bore 49.5 mm • Stroke 44 mm • Displacement 85 cc • Squish 0.9 ± 0.1 • Exhaust timing 191° / transfers 132° • Geometric compression ratio 14.7:1 (actual 8:1) • Recommended advance 17° (1 mm before TDC).

Examples of compatible models: VENT DERAPAGE 50 RR (2025), SHERCO SM 50 RS SILVER (2024), RIEJU MRT 50 SM TROPHY (2024).