Cylinder PINASCO Zuera SS 135cc Vespa Smallframe

Vespa cylinder Pinasco 135cc

Here we introduce you to the two new ones Pinasco Zuera cylinder for Vespa V50, PK, Primavera, etc. in front!

In addition to some innovations in Largeframe Area, such as:

• them Vespa engine case and
• of divisible tubeless rim

offers Pinasco for the 125er Smallframe Models also two new cylinders

Both cylinders were among other things also on the very popular 24h race in Zuera / Spain tested. Hence both cylinders bear the name zuera.

Diaphragm pressure inlet and cylinder sucked into the housing

The variant with Diaphragm direct inlet has been given the surname SRV 135, during the Cylinders sucked into the casing Zuera SS 135 was named.

The Pinasco SS135 let's take a closer look today.

What's in the box

• Cylinder and cylinder head
• Piston, including piston pin, piston ring and locks
• Fastening material cylinder head
• Gasket set cylinder base
• Plug for the cylinder cover

cylinder head

With the quite massive, cast cylinder head the first thing you notice is the completely machined underside. The combustion chamber with the central position of the spark plug is offset by approx. 1mm. The cylinder head is centered on the cylinder via the outer contour of the sealing surface. A cylinder head gasket is not provided. The 8-fold screwed cylinder head and the generously dimensioned sealing surface should ensure a permanently reliable seal even without additional sealing elements. Pinasco recommends a tightening torque of 8Nm both for the cylinder stud bolts and for the additional M25x12 screws on the cylinder head.

Due to the central position of the spark plug, the original opening in the cooling hood must be closed. Pinasco has paid attention to this small detail and includes a suitable sealing plug. Here you need a spark plug with a long thread. In the case of an NGK spark plug, we would use a B9ES or, if you want to ambitiously move your Zuera 135SS around the racetrack, a B10EG

Piston

The 169gr cast piston is equipped by Pinasco with a 1mm rectangular piston ring and 1mm G-shaped fuses.
The hint of the gas flow in the form of the small, beveled surfaces below the piston pin is very cute.
This “trick” was often used on pistons with a long piston skirt before it became fashionable to give the piston an open side contour.
Like many modern cylinders, the piston of the Zuera 135SS also gets an additional anti-friction coating.
Pinasco does not make any experiments with the piston pin. Due to its low wall thickness, the bolt is deliberately designed to be weight-reduced.

Cylinder

At first glance, the design of the overflow channels in the cylinder shows a striking resemblance to the Polini Evolution. On closer inspection, however, you will discover the differences in the design. The angles of the entry surfaces are clearly visible.

Due to the outlet and overflow channel height and an assumed piston backlog of 0mm, there are quite sporty control angles of 125 ° / 185 °.

In contrast to other cylinders, the openings of the overflow channels in the cylinder base are already open.
The cylinder base has a diameter of 61,3mm, so it is not necessary to enlarge the cylinder base bore in the motor housing.

However, as with almost all performance-oriented cylinders, the open overflow channels in the cylinder base also require the fan channel to be adapted on the stator housing.

The one-piece outlet with a width of around 66% is already made for durability. However, we would suspect that the Zuera 135SS is slightly above the Polini Evolution I in terms of performance due to the significantly sportier outlet geometry.
Due to the angle of the overflow channels facing the outlet, the Zuera 135SS also supports exhaust systems that like to reach into higher speed regions.

You can adjust the pinch edge recommended by Pinasco from 1.0 - 1.1mm using the 3 supplied 0,1mm cylinder base seals. When it comes to cylinder head gaskets, Pinasco is discreetly restrained, also when it comes to the seal and the connection to the exhaust. An exhaust gasket suitable for the Zuera SS135 is just as little included in the scope of delivery as the required outlet studs.

A suitable stud bolt for the outlet is best Material from Piaggio .

The combination of M8 exhaust studs and their spacing limits the selection of possible exhaust gaskets.
Unfortunately, Pinasco does not provide a suitable seal.
The PK125 exhaust gasket from Piaggio fits on the flange. However, the outlet of the SS135 is 31mm x 27mm. This creates the PK125 exhaust gasket
not really fitting here due to the smaller inner diameter.
Alternatively, you can also use the BGM exhaust gasket use. With this variant, however, you have to widen the hole stitch in the seal by a few millimeters.

Technical details of the Zuera SS135 cylinder

• Bore 57,5mm
• Stroke 51mm
• Cubic capacity 135ccm
• 5 overcurrent channels
• One-piece outlet, trapezoidal, cord 38,5mm? 66%
• Exhaust stud M8 (not included, we recommend Piaggio)
• Hole stitch outlet flange 52mm (we recommend as exhaust gasket BGM)
• Cylinder base gaskets three pieces in 0,1mm
• Cylinder base Ø61,3mm (suitable for Piaggio)
• Cast piston 169gr, a piston ring 1mm
• Piston pin retainer type G, 1mm
• Cylinder head screwed 8 times (stud bolts + 4pcs. M8x25mm)
• Spark plug 14mm, long thread, recommendation B9ES, B10ES
• Position of the spark plug, central
• Ignition timing 17 ° (recommendation by Pinasco)
• Control angle 125 ° / 185 ° with a squeeze dimension of 1,0mm and a stroke of 51mm

Conclusion on the new Pinasco Vespa cylinder for Smallframe

The bottom line is that Pinasco has one here sporty cylinder put on its feet with little effort good driving performance offers.

Whether with SHB19, Polini CP carburetors and Piaggio or Polini banana or with one keihin 28 and a French - to the Pinasco SS135 can be elicited by the appropriate environment of the carburetor and exhaust, performance ranges from moderate to sporty.