LEADER (engine)

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The LEADER engine is a generation of engines from Piaggio . Leader engines were built between 1999 and around 2010.


Two - wheelers were traditionally equipped with two-stroke engines, which were easier to build, easier to maintain and more powerful than four-stroke engines , which only showed advantages in terms of consumption and emissions . The environmental awareness that began in the 1970s took hold of the automotive industry in the 1980s and later also of the two-wheeler industry, which was met with ever stricter emissions standards , which led to the use of four-stroke engines. In the mid-1990s , Piaggio introduced air-cooled four-stroke engines in the Piaggio Sfera, Piaggio Vespa ET4 and the Piaggio Hexagon , before the LEADER engine was used from 2000, whereby these engines were on a par with the standard two-stroke engines.


The LEADER engine (LEAD.ER, L ow E mission AD vanced E ngine R ange) was introduced in 1999 as an air-cooled 2-valve four-stroke engine and as a water-cooled 4-valve four-stroke engine with displacements between 125 cm³ and 180 cm³ the engine range was later expanded to 250 cm³. Air-cooled motors are commonly referred to as AC (air cooled) and water-cooled motors with LC (liquid cooled). The LEADER engine initially complied with the Euro 2 standard and was used in many vehicles from the Piaggio Group, which is also what it has in its acronym : it has low emissions and is versatile. In 2007 the Leader engine was fitted with an uncontrolled catalytic converter in order to meet the Euro 3 standard. The LEADER engine was replaced by the QUASAR engine in large displacements from 2005 and by the LEM engine type for air-cooled engines in 2012 . Only a few vehicles are currently being fitted with it.

Technical specifications





All engine variants have a piston stroke of 48.6mm, which means that many components can be made the same or very similar. The variation takes place exclusively via the cylinder bore . The exhaust system and thus the exhaust gas behavior have been improved several times. The last engine generation achieved the Euro 3 emissions standard . There are versions with a rear drum or disc brake, air and water cooling have already been mentioned. In addition, there is a long and a short housing (engine swing arm), because this is used to adapt the length of the engine to the vehicle or to the size of the rear wheel. That is why there are two different length vario straps . The gear ratio is adapted to the size of the wheel with the secondary gear pair in the reduction gear, of which there are also two versions. A small reduction gear for short swing arms, which can even be equipped in two versions, namely as a short configuration for 10 "and 11" wheels and in a long configuration for 12 "to 14" wheels and a large one for long swing arms, which is used for 15 ″ and 16 ″ bikes and is also used for the Quasar. Another variation is the transmission output shaft; there are motors with a thin and motors with a thick transmission output shaft.

Weak points

Motors of the Leader generation are considered to be fully developed, reliable and, with normal maintenance, can reach over 100,000 kilometers. Weak points only become visible after tuning the engine or driving accordingly. One such weak point was initially the timing chain for the valve train of the water-cooled 200 cm³ engines, which stretched over time, so that the timing chain tensioner could no longer tension the chain sufficiently. Another structural weak point is the crankshaft bearing shells, which cannot be replaced. In the event of a damaged bearing shell, usually a result of consequential damage from stray metal chips in the oil circuit, the housing half must be replaced. But both occur extremely rarely. The poor cold running properties of the Walbro carburetor, which was used in the early years, are more annoying.


By Malossi , Polini and Kübler there finished sets, to increase the capacity of the leader engine and abzuverlangen him more power. While Malossi and Polini build on the existing piston stroke, Kübler also changes the stroke, which makes it necessary to replace the crankshaft. Kübler uses components that were built for quasar engines and modifies them. Such an intervention in the engine is financially and technically expensive, so that the purchase of the next larger model often has to be considered.

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