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  • M14x1,25, Wrench Width 20,8mm
  • Interference Suppressed / Long thread
  • Similar to BOSCH WR4CC
  • Similar to CHAMPION N3C
  • Similar to DENSO W24ESR-U


Thread type:M14x1,25
Length spark plug thread:19 mm
Thread spark plug:long
Wrench size:21 mm
Electrode material:Nickel
Electrode type:standard
Spark plug with terminal (grommet): 
Protective cap is screwable: 
Heat rating Bosch:WR4CC
Heat rating Denso:W24ESRU
Heat rating Champion:RN3C
OEM numbers (comparison purposes)


B6ES - long reach / town and city use / for a standard engine.


B7ES - long reach / town and city use / for a standard engine.

B8ES - long reach / local and distance use / for a standard or midly tuned engine. 

B9ES - long reach / competition or distance travelling use / for a tuned engine. 

B10ES - long reach / competition or full race use / for a high tuned engine / sidecar use. 

Spark plugs with a 'BR' denomination have a built-in resistance and are designed for use with delicate electronic equipment (such as SIP rev counter / speedo units). 

Spark plugs with a 'HS' denomination are SHORT reach versions (usually utilised for early pre-S1 Lambretta models manufactured between 1947-'57).

Lambretta models that use a SHORT REACH spark plug are: A + B + C / LC + D / LD + E /F + Lambrettino 48.

Lambretta models that use a LONG REACH spark plug are: S1 + S2 + S3 + GP / DL + J (all versions) + Lui Vega Cometa + Serveta.

NGK copper core spark plugs deliver increased heat dissipation for more reliable starts and reduced risk of overheating.


Colder spark plugs are suitable for racing cylinders and use over long distances. In this context, the sound thermal output of heat to the cylinder head takes place, there is a risk of sooting, however.


Hotter spark plugs are used in sport and standard cylinders. The reach their operating temperature quickly but can also overheat.

Most spark plugs for scooters have a M14x1.25 SW 20.8 thread and are either long thread (19mm) or short thread (12.7mm).


Please note: putting a long thread spark plug in a short thread cylinder head will damage the piston.


Copper spark plugs are the most popular spark plugs on the market and are a useful tool in every day scooter life. Rapid operating temperature, constant performance, optimal reaction during changing driving conditions, for example town driving, and last but not least, fuel savings are their advantage.


The copper core of the middle electrode conducts the heat well and protects against thermal overload. Nickel-chrome-alloy protects the copper core against corrosion and guarantees high level protection against wear and tear and spark erosion.



    This is a resistor type spark plug that is needed for SIP Speedos.

    Product fits the following vehicles:-

    Moto Vespa PX 125 T5 Sport Elestart Eng 108M
    Moto Vespa PX 125 T5 Sport (Engine 98M)
    Vespa PK 50 XL2 automatica (V5P2T)
    Vespa PK 50 Automatica (VA51T)
    Vespa PK 80 S Automatica (VA81T)
    Vespa Cosa 125 CL (VNR1T)
    Vespa Cosa 125 CLX (VNR1T300)
    Vespa Cosa 125 CLX (VNR1T301)
    Vespa PX 125 T5 (VNX5T)
    Vespa Cosa 200 CL (VSR1T)
    Vespa Cosa 200 CLX (VSR1T300)
    Vespa Cosa 200 FL (VSR1T301)
    Vespa PK 50 S automatic (VA51T)

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