for GILERA/ PIAGGIO 50ccm 2T AC/ LC
stroke 39.3mm
conrod 85.0mm
pin 12mm
for crankcase PIAGGIO/C-One/RC-One

TUNING RACE – for professionals
Product description
Together with the cylinder and piston, thecrankshaft represents the beating heart of any internal combustion engine. It is amongst the hardest working components and the conversion of the pistons stroke to a rotary movement places the highest demands on both quality and the care taken during construction.
The crankshaft should also be well balanced to reduce any unwanted vibrations and the oscillating mass kept to a minimum to support an efficient delivery of the power created by the motor.
The big-end bearing rotates at the same rate as the motors RPM, receives lubrication from the petrol/two-stroke oil gas mixture and must withstand two abrupt changes in direction of the piston for each motor revolution.
The crank-pin, connecting both crankshaft webs with the con rod, has to be pressed into the webs with a certain clearance to the openings in the webs. If this connection is not strong enough the crankshaft can twist and the crankshaft webs become misaligned and seize.
To ensure the big end bearing receives sufficient lubrication the big end of the con rod should be provided with slots to facilitate this.
Thesecrankshafts are produced forOTTOPUNTOUNO in Italy and satisfy all of the above listed demands. They have concentrated their efforts to provide the highest quality combined with tried and tested technological features. This crankshaft includes a con rod of extremely high quality and they are made more enduring with an intensive polishing procedure that provides a more stable molecular structure. The smooth polished flanks of the con rod also help reduce turbulence. The polished con rods also have been optimized with a reduction in weight. They possess a gas-flowed profile and been modified around the big end to improve the bearings lubrication.Crankshaft
OTTOPUNTOUNO
R-18 for original PIAGGIO or MALOSSI C-One engine case.Stroke: 39,3mmCon-rod: 85mmOuter diameter: 73mmWidth: 41mmWeight: 1,6 kg