Full Pipe Help with jets

[400exrapes]

I can jet a carbuerator fine but i dont know the stock size and my friend just ordered an hmf full system and thats all for his mods. What size pilot and main jet do you all run and recommend? It's clearly winter right now with temperatures ranging anywhere from 0-50 degrees farenheight and our elevation is about 200-300 feet above sea level. Where should we start

[exrider12]

check the FAQ:rolleyes:

[tedwilley]

1. Read the FAQs
2. Search this forum for 'jets', 'jetting', 'rejetting', etc. there are posts from some who offered their jet sizes.
3. HMF recommends a 125(?) probably way too big, especially as a starting point.
4. I am about your elevation, but we don't get much below 45 deg F in the Winter, here what I am running:
HMF full system, K&N, no lid, AMR stage III CDI(rev box)
Main jet 112
Needle clip on third position (2006-2008 do NOT have adjustable needles, you'll need an aftermarket needle)
Fuel screw 2-3/4 turns out
Pilot jet stock 42

Stock jetting is:
Main 96
Needle 2nd position
Fuel screw 2-1/2 turns out

My first guess would be a 108 main, third needle position, 2-1/2 turns on the fuel screw. That should get you started.
The fuel screw in underneath the carb towards the front and requires a special tool to adjust it without removing the carb, the fuel screw head is shaped like the letter D. With the carb removed, you can turn it with small needle nose pliers (or a small flat screw driver in slow partial turns)

[jrafter]

my kids 250 jetting ended up being 97.5 main and shimed the needle jet.

the needle jet ended up being the most importanted.