VMC CRONO 187cc Cylinder Kit + 60mm Stroke Shaft + 10-Spring ERGAL Clutch for Vespa Large

for Vespa 125 GTR 2°/​TS 2°/​150 Sprint V 2°/​Super 2°/​P125-150X/​PX125-150 E/​Lusso/​MY/​Cosa

SIP code: 45021531

for clutches "10 springs vmc keyed", " SIP Race Supersport/​BFA" with keyed bushing

rotary disc valve

stroke: 60.0mm

connecting rod: 110.0mm

two piston pin roller cages: 16x20x20mm and 15x20x17.87 mm

piston pin Ø 16mm and 15mm

Ø Alternator side oil seal seat: 24 mm

Ø Bearing seat on alternator side: 20 mm

Thread on the alternator side: M12x1.25

timing: 125°/-5° at tcm

SIP PREMIUM 60 stroke crankshaft, 110mm connecting rod, keyed for Vmc Crono and large Vespa 125 - 150 PX crankcase 45021530

This shaft has the keyed clutch pin dedicated to the Vmc 10 spring keyed clutches and to the dedicated Sip performance clutches.

Along with the cylinder and piston, the crankshaft is the beating heart of any internal combustion engine. It is among the hardest-working components, and converting the piston stroke into a rotary motion places the highest demands on both quality and the attention to detail required during construction.

The crankshaft should also be well balanced to reduce any unwanted vibrations and oscillating mass kept to a minimum to support efficient delivery of the power created by the engine.

The large end bearing rotates at the same speed as the engines RPM, receives lubrication from the gasoline/two-stroke diesel mixture, and must accommodate two sharp changes in piston direction for each engine revolution.

The crankpin, connecting both crankshaft legs to the connecting rod, must be pressed into the cores with a certain distance from the openings in the cores. If this connection is not strong enough, the crankshaft can spin and the crankshaft webs can become misaligned and seize.

To ensure that the big end bearing receives sufficient lubrication, the big end of the connecting rod should be provided with slots to facilitate this.

This brand new range of performance crankshafts is manufactured for SIP in Italy and meets all the requirements listed above. We have focused our efforts on providing the highest quality combined with proven technological features. Each crankshaft is specifically balanced to match the stroke, connecting rod length, and scooter model for which it is intended.

The crankshafts available in this range can be divided into two main types. The "Premium" ones feature a high-end "standard" connecting rod, which means its surface finish remains unchanged. They are equipped with grooves and lubrication holes for the large and small bearings, respectively.

The "Performance" crankshaft models include a premium-quality connecting rod and are enhanced with an intensive polishing process that provides a more stable molecular structure. The smooth, polished sides of the connecting rod also help reduce turbulence. The polished connecting rods have also been optimized for weight reduction. They feature a gas-flow profile and have been modified around the large end to improve bearing lubrication.

PX 60mm long stroke crankshaft

The 60 mm stroke provided by the long-stroke crankshaft for the 200cc Vespa models is 3 mm longer than the original crankshafts. This increases the cubic capacity of the installed cylinder by approximately 5%. The improved stroke-to-bore ratio not only increases power, but also significantly improves torque output. The crank is designed to improve torque-rich road engines, and the inlet port timing on the disc valve band is only slightly longer than that of the original type. This allows the engine to maintain decent performance at low revs and is also relatively simple to correctly set up. Backfire from the crankcase is also kept to an acceptable level. The disc valve disc is specially designed to make gas flow through the crankcase more efficient.

Another aspect in the development of crankshaft networks was to provide more effective balancing and a smoother running engine.

Bottom line: The ideal crankshaft for delicate and reliable tuning projects.

Tip: Don't forget to replace the crankshaft bearings and oil seals when upgrading your crankshaft! The perfect connection between the crankshaft and the clutch, for all Vespa largeframe models.

Without key but with an M14 fixing nut.

All SIP crankshafts and clutches featuring this interlocking connection are compatible with each other. With this system, the components are locked together and held in place by the M14 retaining nut, eliminating the need for a key. On original crankcases, a 3.5 mm thick spacer disc must be placed between the clutch and the bearing; with our SIP BFA crankcases, a thinner 2.5 mm spacer disc is used.

Conclusion: a complete solution, which eliminates once and for all one of the weakest links in the transmission of Vespa largeframe engines.

VMC 10-spring ERGAL clutch for Large Frame Vespa - Fitted for Piaggio Vespa "COSA" sprockets

"Ergal" basket with hard anodization specifically for dedicated VMC clutch discs or for the "CR80" model discs

Internal bushing in KEYED steel with hardening treatment complete with bushing and washer.

Specific fitting for SIP Performance shafts

Weight of the complete clutch without gear 1 KG

This bushing solves all the problems with the traditional keys of the Vespa large frame shafts.

Complete with discs, disc pusher with bearing.

Internal steel spider with hardening treatment complete with bushing and washer.

- 4 aluminum conductors with specially made carbon/kevlar friction material and "CR80" disc type teeth.

- 4 laser-cut steel driven discs to have the most precise pinion/disc coupling possible.

Clutch pack closing ring in laser-cut harmonic steel with holes for seeger caliper.

2 sets of 10 springs with different loads:

- with the set of 10 soft springs the clutch can withstand power of approximately 20hp

- with the set of 10 hard springs the clutch can withstand power of approximately 35hp

- with the set of 10 extra hard springs the clutch can withstand power of approximately 45hp

N.B.: The clutch is only suitable for Piaggio 8-spring "Cosa" type clutch discs and sprockets.

THE PINION IS NOT INCLUDED IN THE KIT