Your not going to be able to get much outta that blaster... the only things off the top of my head i can suggest are the usual mods to help it breath better...
Exhaust, intake, reeds.
If you want to spend a bit more and mill the head to up the compression ratio a bit you can do that but depending on how much you hvae milled off depends on the type of gas you need to run..
The other things as well that arent motor related that will make you have more fun enjoying your ride is obviously a properly setup suspension and some lighter paddles... You might try some Paddla Brats.. they are one of the lightest paddles out there and you will feel the diffrence.