I changed mine. No light. I didn't see anything saying not to.
Yeah look on there sites it does say not to ? But screw it if you did not get any lights in a give it a shot I think I got it tuned pretty good just think if I up on the green a little a should be good to go. How long have you been riding with the green changed ?
the lights mean more or less fuel to correct the fuel to air ratio , i got a auto meter to be able to dial inn my z to the proper setting , green yellow red , lights are fuel through the power band , i snorkeled my z , fuel to air is supposed to be around 14 ,14.4 at idle , the closer you can dial in the fuel to 13 during the hole power band the better the performance you will get , the lower the number on the gauge you need to take out fuel to get the proper setting , same as the higher the number on you gauge the more fuel you haft to add to bring back to 13 during the powerband , i have my z dialed in almost perfect , the gauge comes with its own 02 censor you haft to install into the exhaust pipe , but is not that hard , comes with its own bung to weld in , installation was about 1.5 hours including the weld time , trust me the gauge is well worth it , auto meter fuel to air