[CRFrider]

What are the modifications i should do right as i get my bike? For example, taking the baffle plate out.

[Guest]

First modification is information. I would buy a manual for the bike. Then, read it.
Then, all you really need to do is the following:
1.)replace the stock air filter (White Bros or Twin Air are good choices),
2.)remove the airbox snorkle from the top of the airbox,
3.)pull the exhaust baffle out of the exhaust pipe
4.) replace the stock main jet with a 115
5.) raise the needle 1 clip richer.

The service manual will explain the what's, how's and where's thouroughly. You should notice an immediate difference in the bike when your done. Have fun!!