Big Bore Cylinder Kit with Head Ø 47,6 mm, Pin 12 mm, Flat Head Piston
Redesigned intake and exhaust ports
Redesigned piston to maximize inlet flow
Reinvented and Patented Athena fixing system
Race Use Only Product - Please check details on the "Race use only" footer's section
WARNING: the cylinder head and base gaskets contained in the kit are specifically developed for Athena cylinders kits. Whenever the cylinder kit is disassembled, replace the gaskets with the specific Athena spare gasket kit: DO NOT use OE replacement gaskets.
Description
Athena is pleased to announce an absolute novelty in the world of air cooled vertical Yamaha-Minarelli engines and therefore for legendary applications such as MBK Booster / Yamaha BW’s or the iconic Aprilia SR*.
With this brand new big bore cylinder kit, Athena R&D department brings on this cylinder technical solutions usually applied only on high performance engines, such as on the 2T Racing GPs. The multiple innovative technical solutions introduced in this project allow to reach performances never achieved before with this engine.
With this new cylinder kit Athena is introducing many solutions never seen before on these applications. The result is just the best performing cylinder kit ever designed in its category.
A REVOLUTION ON THE PORTS
Athena’s technicians wide experience in the 2T sector allowed them to approach this cylinder challenging the traditional design. The intake and exhaust ports have been totally redesigned: analyzing the thermo-fluid dynamics of the engine, overall performances have been highly improved in terms of power and torque, achieving new levels for the first time ever. The intake port is reinvented, adding a CNC machined fifth port to grant a higher gas flow incoming in the combustion chamber.
Using the innovative fixing system directly on the crankcase without using stud bolts, Athena developed an exhaust outlet with a bigger oval shape and side auxiliary ports. This solution has been applied for the first time ever on this kind of cylinders.
REINVENTED PATENTED FIXING SYSTEM
The regular head and cylinder tightening based on studs has been eliminated introducing a new system of special bolts pretty close to the ones used in the high-level performing engines. Tightening the cylinder to the crankcase (Racing type) with these bolts and a special Allen key leads to a reduction of the thermal expansion of the cylinder, bringing a more efficient tightening and on the other hand allows the sophisticated redesign of the exhaust port that makes this product so special and unique.
NEW RACING PISTON
The flat head piston has been developed focusing in particular on the interaction with the intake. The CNC machined opening on the piston skirt is designed to maximize the inlet flow, to allow greater pressure on the pump casing and better lubrication of the needle bearing.
Technical features
Bore Diameter (mm) | 47.60 |
Compression Ratio | 13.8:1 |
Displacement (cc) | 70.00 |
Vehicle compatibility
APRILIA AMICO 50 cc 1996/1998 |
APRILIA SR FINO 1994 MOT. VERT 50 cc 1994 |
FANTIC PONY SR 50 cc |
GARELLI BIG WHEEL 50 cc |
GARELLI PONY 50 cc |
GARELLI SR 50 cc |
ITALJET ASCOT 50 cc |
ITALJET ASTRA 50 cc |
ITALJET BA ZOOKA 1 50 cc |
ITALJET PISTA1 50 cc 1995 |
ITALJET PISTA 2 YANKEE 50 cc 1995/1996 |
ITALJET REPORTER 50 cc |
ITALJET SCOOP 2/3 50 cc |
KOTIR SR 50 cc |
KTM CHRONO 50 cc |
LEM FLASH 50 cc |
LEM GHIBLI 50 cc |
LEM TORNADO SS1 50 cc |
MBK BOOSTER CW 50 cc 1990/2002 |
MBK BOOSTER CW L 50 cc 2001/2003 |
MBK BOOSTER CW L SPIRIT 50 cc 2003 |
MBK BOOSTER CW NAKED 50 cc 2003 |
MBK BOOSTER CW R ROAD 50 cc 1994/1995 |
MBK BOOSTER CW RS NG 50 cc 1995/2003 |
MBK BOOSTER CW RS NG EURO1 50 cc 1999/2000 |
MBK BOOSTER CW RS NG KAT 50 cc 1999/2000 |
MBK BOOSTER CW RSP ROCKET 50 cc 1997/1998 |
MBK BOOSTER CW RSX TRACK 50 cc 1996/1998 |
MBK BOOSTER CW SPIRIT 50 cc 1996/2000 |
MBK BOOSTER CW SPIRIT EURO2 50 cc 2002/2003 |
MBK BOOSTER CW SP SPIRIT EURO2 50 cc 2002 |
MBK CR Z TARGET 50 cc 1991/1995 |
MBK CT S / SS SORRISO 50 cc 1991/1995 |
MBK EW STUNT 50 cc 2000/2002 |
YAMAHA BW'S 50 cc 2007/2016 |
YAMAHA BW'S BUMP 50 cc 1997/1998 |
YAMAHA BW'S NAKED 50 cc 2003/2009 |
YAMAHA BW'S NEXT GENERATION 50 cc 1997/2003 |
YAMAHA BW'S NEXT GENERATION KAT 50 cc 1999/2000 |
YAMAHA BW'S ORIGINAL EURO2 50 cc 2003 |
YAMAHA BW'S ORIGINAL / SPY 50 cc 1997/2002 |
YAMAHA BW'S R 50 cc 2001 |
YAMAHA CR Z TARGET 50 cc 1991/1995 |
YAMAHA CT SUPER SPORT 50 cc 1990/1995 |
YAMAHA CW BW'S ORIGINAL EURO2 50 cc 2002 |
YAMAHA CW L BW'S 50 cc 2003 |
YAMAHA CW RS SPY 50 cc 1995/1998 |
YAMAHA CW SP BW'S ORIGINAL EURO2 50 cc 2002 |
YAMAHA EW SLIDER 50 cc 2000/2002 |