When I was removing the sprocket cover on the 90R 4 stroke, it had a box on the inside cover and when I looked it up it was the emission control valve. Would it hurt anything if I plugged this up from the exhaust and fabbed up a nice cover or by removing this, would I have to rejet??? Thanks

 

Does anybody have an idea??

 

I haven't tried it their atv's but on their scooters I have plugged them off and they run alot better.

 

Just an update, I removed the Emission control valve and the bike seems to run a little better. Does not seem to have hurt anything at this point. Thanks for the help kpracer