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TnT explosive tester
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No real reason but ive read a little bit on here about the valve in the exhaust

but what the hell is it for and what does wiring it open actually do?
 

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As I understand it, the exhaust valve works in conjunction with the flaps in the air box to quieten the bike at a predeteremined rpm (I think its ~4300).

There is an EU regulation which requires new bikes to be quieter than XYZ decibels (dB) at this rpm. (There is a stamped label near the headstock with all the numbers on). Manufacturers make their bikes as quiet as possible at this rpm in order to pass the test. By shutting the exhaust and airbox the noise is reduced but a consequence is a flat spot

Of course, EXUP type valves also help boost low to midrange but the Nelli isn't short of that. So wiring it open helps fix the flat spot and doesn't affect the low end grunt badly (if at all).

Finally, the ECU is mapped to expect the valve and flaps to be in place. I assume that you have to re-map to get the full benefits - Over to the clever people for the answer to that one
 
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