Plug electrical

[JJH]

On my brothers v85. Took it off. Bike sounds much better. Was a very harsh sound from exhaust. Anyone know what it is? Just hooked around top box for ease of photography. Thanks. JJH

 

[squibb34]

Here is the wiring diagram ........... https://www.thisoldtractor.com/mg_manuals/wiring_diagram_v85-tt_en.pdf

Presumably some form of aux rear lighting, but I can't make sense of the colour coding.

 

[JJH]

Found out what this is. It’s a device that makes the engine management think it’s colder than it actually is so the engine runs richer. I can’t see for the life of me why it makes the exhaust sound harsher. Now if it advanced the ignition…..

 

[Jazbee]

Found out what this is. It’s a device that makes the engine management think it’s colder than it actually is so the engine runs richer. I can’t see for the life of me why it makes the exhaust sound harsher. Now if it advanced the ignition…..

Yes it's a Mistral V-Twin boost JJH, I've one fitted but does not affect the exhaust, its designed to overcome some issues with lean settings for euro 5 emissions regulations. I've a full mistral de-cat exhaust though so maybe not a good comparison with stock system.