jetting 4 gutted stock pipe and air box lid removed

[tnc110]

I ride at about 3500 to 4000' elevation. the stock pipe is gutted now. Im thinking about pulling the lid off the box. As of now the carb is stock. Do i need to rejet since the pipe is gutted at this elevation or is it ok. If i pull the lid will it need to be rejeted. If so what jet?

[cataway]

do you know what jets in it now ? mine was a 130 till i removed the box lid ,then it needed a 142 but that was at 900'

[tnc110]

I dont know what is in it now...whatever came stock i would imagine.

Am I right in thinking the higher the elevation the more lean you can run an engine?

[cataway]

the higher you go the smaller the jet you need