jetting 03 raptor

[brad_400ex]

I was wondering if i put a slip on pipe on my 03 raptor if i should rejet it. Can i just put a main jet or do i have to get a jet ket. Thanks

[Glenyzracer25]

with a slip on pipe you may be able to go up one jet size. if you go much larger it will bog or flood if you climb hills or do wheelies. i wouldnt mess with the needles or pilot jets.

[tater_kamik]

you should be ok with just changing the main jets. you may have to move the clips on the needles though. follow the mfg instructions if it has any, then rejet as needed from there. as far as a jet kit, i honestly dont like them, i just buy all of the jets, needles, etc i need and have them in a kit that way i always have the right stuff and a few extra. a jet kit will work though if you need it, they are made to have the jet sizes needed for general mods

[Dan660R]

Is anything else going to be done or already been done? Like upgraded air filter, or cutting of the snorkel for more air?

If you do have any air-mods, I would just jet it appropriately with a jet kit or buy the jets and parts separately if you know what you need. If you dont have any air mods or dont plan to mod them, then you can try it out as is, but do a plug check.

[brad_400ex]

The previous owner drilled holes in the air box, other than that i just plan on putting on a slip on. How many sizes up a jet do you think i should start with?

[Dan660R]

If you have holes in your airbox then you might as well mark it off as an intake mod...

With my '01 Raptor, I had a filter and a slip on, and I ran 146/148 dynojets. Dont confuse those numbers with Mikuni's. My current setup I believe is 155/160 mikuni jets, again with a K&N and a slip on. I also change the pilots to the 25mm jets, from the smaller 22.5mm jets, runs a lot better down in the low rpm range.

I went with a GYTR kit this time around cause of the deal I got, and I seem to like it.

[300exryder]

I would buy the jets individually. I'm surprised your Raptor hasn't been having any problems in the 0 - 1/4 throttle range - you definitely should up the pilots to 25's after the pipe. Might as well while you are in there...