Cylinder head UMA 200cc Superhead Yamaha/Minarelli YI-3/4 Motoren (Yamaha YZF-R, WR, MT 125, Beta RR, usw.), 65-70mm Zylinder

This racing cylinder head from UMA was specially developed for cylinders with bores between 65 and 70mm. In other words, for displacements from approx. 200ccm3. The cylinder head is pre-assembled, i.e. the intake and  exhaust valves as well as the rocker arms and rocker arm shafts are already installed. Speaking of valves: The intake valves have been enlarged from 19.5mm to an enormous 23mm and the exhaust valves from 17mm to 20mm . This alone results in a significantly better filling of the engine. The combustion chamber is apple-shaped, which results in a higher compression ratio and therefore a significant increase in performance. In addition, the cooling circuit has been optimized to ensure better heat dissipation. 

A sharp camshaft suitable for the valves is included in the scope of delivery.  

Scope of delivery

• Cylinder head
• Valves (pre-assembled)
• Camshaft with main bearing
• Rocker arm (pre-assembled)
• reinforced valve springs (pre-assembled)
• Head gasket
• Exhaust gasket
• Hose clamps
• Intake manifold for injection engines (For carburetor engines, a different intake manifold must also be ordered)