Tuning Cylinder Kit ZT75N Stage 2 (75cc) - for Simson KR51/1 Schwalbe, SR4-2 STAR, SR4-3 Sperber, SR4-4 Hawk

Cylinder kit ZT75N Stage 2 Features: - Original optic cylinder with coated aluminum bushing - High quality material for heat sink and running bush - Improved heat dissipation thanks to fine-blasted surface and coated aluminum bushing - Long shelf life approx. 10 tkm per Piston, several oversizes are available) - Vmax 95-100 km/h - approx. 11.5hp Note: The bore of the original motor housing must be extended to 54 mm (screw the motor housing). A BB crankshaft should be used. The original coupling must be reinforced (conversion 5 KR51/1 multi-plate clutch) A tuning air filter must be used (Air filter KR 51) when installing a 21mm carburetor, please mount it directly on the cylinder and the original Omit the intake manifold. Only Motul 800 2T Road Racing may be used as a mixed oil! Use rubber buffer (10070259) for exhaust mounting! Breaking of the manifold thread possible with rigid attachment! Scope of delivery: - ZT75N cylinder (release diameter 54mm) - ZT75N cylinder head (outer-centered) - ZT 1-ring piston Ø49 mm incl. ring, bolts & clips - carburetor flange gasket - 2x Cylinder base gasket - 2x carburetor flange studs For a long time there were very few, more powerful cylinders for the KR51/1. On the one hand, this is due to an unfavorable channel routing, on the other hand, you quickly reach the thermal load limit, especially with more powerful kits. With only 2 oversize pistons, the longevity of such gray cast iron cylinders was also limited. The heat sink and the liner are made of a high-quality cast aluminum. The bushing is coated in a special process, which makes it extremely robust and optimally protects against wear. The thermal conductivity is also much higher than in a cylinder variant with gray cast iron bushing. In addition, the heat dissipation is further improved by a radiated, slightly rough surface. This means that the 2 core problems could already be eliminated through the use of new technologies. The timing and channel cross-sections were designed for high torque from the speed cellar and wide power band to harmonize perfectly with the 3-speed gearbox. The driveability from the speed cellar is absolutely identical to our "old tuning cylinders". In addition, however, the performance in the middle and upper speed range could be significantly increased, which in the end result enables a performance band and a performance development, which is otherwise unmatched in this class.