CRONO 187cc Cylinder Kit CNC Head and 60cc Crankshaft

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

for SIP Race Supersport/​BFA clutch for splined connection

rotary disc valve

stroke: 60.0mm

connecting rod: 110.0mm

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

Piston pin Ø 16mm and 15mm

Ø Alternator side oil seal seat: 24 mm

Ø Bearing seat alternator side: 20 mm

Thread on the alternator side: M12x1.25

Timing: 125°/-5° at tcm

clutch side teeth

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

This shaft has the clutch pin keyed 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 one of the hardest working components, and the conversion of the piston stroke into a rotary motion places the highest demands on both quality and attention to detail 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 revolution of the engine.

The crank pin, 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 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 produced for SIP in Italy and meets all the requirements listed above. We have concentrated our efforts to provide the highest quality combined with proven technological features. Each crankshaft is specifically balanced to suit the stroke, connecting rod length and scooter model it is intended for.

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

The "Performance" crankshaft models include a very high quality connecting rod and are made more durable with an intensive polishing procedure that provides a more stable molecular structure. The smooth and polished sides of the connecting rod also help reduce turbulence. The polished connecting rods have also been optimized with a reduction in weight. They have a gas flow profile and have been modified around the big end to improve bearing lubrication.

PX 60mm long stroke crankshaft

The 60mm stroke provided by the long stroke crankshaft for the Vespa 200cc models has 3mm more stroke than the original crankshafts. This increases the cubic capacity of the fitted cylinder by about 5%. The improved stroke to bore ratio not only increases power but also significantly increases torque output. The crank is designed to improve torque-hungry road engines and the inlet port timing on the disc valve band is only slightly longer than on the original type. This allows the engine to maintain decent low-rev performance and is also relatively simple to set up correctly. The ‘blowback’ from the crankcase is also kept to an acceptable level. The disc valve disc is specially designed to make the 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 equipped with this interlocking connection are compatible with each other. With this system the components are locked together and held in place by the M14 fixing nut, eliminating the need for a key. On the 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 Clutch 10 springs ERGAL for Vespa Large Frame - Fitted for Piaggio Vespa "COSA" model sprockets

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

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

Specific fitting for SIP Performance shafts

Weight of complete clutch without gear 1 KG

With this bushing all the problems with the traditional keys of the Vespa large frame shafts are solved

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 load:

- with the set of 10 soft springs the clutch resists powers of approximately 20hp

- with the set of 10 hard springs the clutch resists powers of approximately 35hp

- with the set of 10 Extra hard springs the clutch resists powers of approximately 45hp

N.B: the clutch is only fitted with Piaggio 8 spring "Cosa" type clutch discs and pinions

THE PINION IS NOT INCLUDED IN THE KIT