BGM PRO 177CC CYLINDER FOR VESPA PX125/150 (ALSO WITH ELECTRIC STARTER)

New version of the proven BGM177 cylinder for Vespa PX125/150. Now also suitable for vehicles with electric starter.

Scope of delivery:

• Cylinder
• Piston
• Piston rings
• Piston pin
• Piston clips
• Gasket kit

EVERYDAY PERFORMANCE BOOST
The BGM177 cylinder is a very powerful, durable, and fully everyday-compatible conversion cylinder. It covers a very wide range of applications. Simply by replacing the cylinder, you can more than double the performance of the 125cc standard engine and wonderfully ride the large torque curve. At the same time, the exact same cylinder can transform the engine into a beast with over 20PS if it finds the right environment (carburetor, exhaust, crankshaft). This makes the cylinder a perfect basis for beginners to expand it further according to their needs.

The BGM PRO 177 replaces the original cylinder, and the conversion can be easily and reliably revised if necessary. With its large displacement of 177cc, the BGM PRO 177 always offers a confident and relaxed driving experience. The engine runs powerfully like a 200cc machine, but more sharply, yet with exactly the same reliability and durability. It achieves this by working in the same speed range as a standard engine. Low fuel consumption and the associated high range are another bonus of the BGM PRO 177 cylinder. The cylinder is designed to be fully compatible with all standard components. The only adjustment that is made is a change of the carburetor jetting and a spark plug with an adjusted heat value.

FEATURES
The BGM PRO 177 cylinder is a hard ceramic coated aluminum cylinder with a 63mm bore. The coating (Nickel-Silicon-Carbide) ensures an extremely hard and durable running surface. The piston has a high silicon content. This means it has a lower thermal expansion, is more wear-resistant and thermally very stable. Two 1mm thick piston rings minimize friction and thus increase performance and speed resistance.

• Cylinder material: Aluminum

• Running surface: coated with Nickel-Silicon-Carbide

• Bore: Ø 63mm

• Displacement 57/60mm stroke: 177/187 ccm

• Piston: Cast piston with high silicon content and two 1mm steel piston rings

• Recommended squish clearance: 0.8- 1.2mm

FURTHER TUNING

The cylinder kit is designed as a plug 'n play solution. However, the cylinder still has a lot of potential for improvement with full reliability. With a 24mm carburetor of the 200cc models and a BGM Big Box Touring exhaust, the performance is already around 15 PS and the torque at 17 - 19Nm at the rear wheel. The BGM PRO 177 reacts very gratefully to all performance-enhancing measures such as:

• A suitable exhaust system (BGM BigBox Touring (BGM1011TR), Polini Box (P2002018))

• A larger carburetor (BGM PRO Faster Flow SI24 (BGM8570))

• Crankshafts with extended inlet timing (BGM031120G) and/or more stroke (BGM031121G)

• An optimized flywheel (BGM8025RT)

• Optimizations to the intake manifold (reaming the intake port)

• Enlargement of the transfer port areas in the cylinder base gasket and in the engine housing (The transfer ports on the cylinder base have a shoulder. This means that the ports on the cylinder match those on the engine housing. The shoulder can be easily removed to utilize the full cross-section of the ports)

MORE DISPLACEMENT AND PERFORMANCE
The cylinder is already prepared ex works to be used with a crankshaft with a larger crankshaft stroke (60mm instead of 57mm as standard). This increases the displacement to a whopping 187ccm and the performance-determining timing angles of the ports are enlarged. With corresponding crankshafts and further modifications to the engine, the cylinder can also be used without any problems with an even larger stroke (up to 64mm, see crankshaft KINGWELLE). With this, it reaches the full 200cc, but requires a membrane inlet due to the necessary crankshaft (e.g. from MRP Racing 3331680 or 3331682).

IGNITION
Due to the optimized CNC cylinder head with narrowly tolerated squish clearance, the BGM PRO 177 cylinder is already very efficient and powerful. The standard ignition components of the Vespa PX models up to model year 2011 are therefore ideal for permanent operation. Special ignition modules or variable ignition timing are therefore not necessary for high performance and reliability. A simple static ignition setting to 19° BTDC is recommended, but the cylinder can easily be operated with the 18° advance, as set ex works on the PX125E models. Models from 2011 onwards use ignition components from China that do not allow very high speeds. Here, the ignition baseplate, the flywheel and the CDI can be upgraded to the old, better version. We also offer a complete set here (BGM666PXL). However, the possibility of using an electric starter is lost with this (the flywheel does not have a toothed ring for the E-starter).

TIMING ANGLES

• 57mm stroke: Transfer 118°, Exhaust 171° (with foot gasket 0.2mm, no head gasket)

• 60mm stroke: Transfer 123°, Exhaust 173° (with foot gasket 0.2mm, head spacer 1.5mm)

• (Head spacer for 60mm stroke not included, optional available, see accessories)

TRANSMISSION
Many customers extend the gear ratio in the follow-up, even at low performance levels, in order to be able to utilize the newly gained power of the engine even better. This is done by simply replacing the clutch pinion. This is relatively easy to reach after dismantling the rear wheel and the clutch cover behind it. Alternatively, a reinforced clutch type can also be switched to directly (see accessories). After that, the gears can be accelerated much further and the achievable final speed is increased. The engine has so much power that the acceleration usually improves as well, because less or faster shifting is required.

Generally, the gearing can be longer than usual in the 177cc class due to the high torque. If a tour-oriented exhaust with early support is used (BigBox Touring, Polini Original Box), a clutch pinion with 23 teeth should be used on a PX125 at least. We specifically offer these for the original primary gear with 68 teeth (see accessories). Engines with long-stroke crankshafts also easily pull a 24/65 ratio on PX125 transmissions.

CONCLUSION
Universally usable plug 'n play cylinder kit with early performance, wide speed band, reliability like an original cylinder, low fuel consumption and thus an unbeatable price-performance ratio!

About the Manufacturer BGM

BGM is a leading brand for high-quality spare parts and accessories for scooters, motorcycles and classic Vespa models, which stands for quality, precision and innovation. With a uncompromising “Made in Germany” philosophy, BGM develops durable products in collaboration with leading engineers and under strict quality controls. Whether restoring classic vehicles or tuning modern scooters – BGM is the first choice for demanding drivers. Thanks to first-class workmanship and a broad assortment, BGM offers ideal solutions for performance, everyday life and individuality.