carb re-jet?

[kawboyCAFE]

hey guys, gotta question. if i put a K&N air filter in, and punched out one baffle plate, should i re-jet the carbs. i know some people say you dont technically have to, but should i? re-jetting isnt that hard, but i dont want to if i dont have to. know what i mean? plus, will re-jetting kill my gas mileage? what do you guys think.

[Triangles]

From my experience on my GZ250, I opened up the exhaust and did a K&N filter, rejetted and it just made the bike louder and took a maybe 15% hit in fuel economy without much of a noticeable performance boost. From what I understand of how the engines work the reason your mileage goes down is not because you're necessarily running richer, its that with less intake restriction and exhaust restriction some of the some of the incoming air/fuel gets sucked out the exhaust while the exhaust and intake valves overlap. I don't claim to be any expert, so take the last sentence with a large grain of salt. I don't know if it's true but it makes sense.

I don't think what you've done would change things enuff to warrant a re-jet. Now if you got rid of the air intake box and put some K&N pod filters on, I'd definitely re-jet. As long as it rides fine I wouldn't try to fix it cause it isn't broke. If you're really concerned, ride around for a while and then check the plugs. If they indicate you're lean, I'd try shimming the needle jet before bumping up the main jet, but that's just me babbling on here in the middle of the night... I need some sleep.

[kawboyCAFE]

thanks for the info.

[Triangles]

btw I forgot to mention I ended up going back to stock with the GZ250.