Im pretty sure that it needs to be rejetted i have a yoshi pipe and a hotcam stage 2 that i just put on. i didnt jet it i wanted to see how it would run without jetting.
i live in Ithaca New York and i have no clue the elevation. im guessing high theres mountains everywhere and i live on one or a big big big hill. right now its been about 70 degrees out. anyway my problem is when i drive it bogs down when i accelerate. and when its on choke and i give it throttle it sometimes back fires. but with no choke and in neutral gassing it it goes up to the rpms fine.

 

Jetting isn't optional, it's not a modification. It's required to keep the motor from burning up.