Whats the difference between a pilot jet and main jet?

[srooney_12]

Whats the difference between a pilot jet and main jet?

[4StrokinJay]

Pilot affects throttle from idle to 1/4 and main is 1/2 to WFO.

[srooney_12]

do thet come with a dynojet kit

[nosliw]

pj - no to 1/8
mj - 3/4 to wot

ive never bought a kit before so i cant help you there

[F-16Guy]

Originally posted by srooney_12
do thet come with a dynojet kit
Main jet yes, pilot jet no. I personally wouldn't waste my money on a jet kit. You will end up with a whole bunch of jets that you will never use. Ask around here about jetting for the mods you have, and then buy a few jets in the range of what people suggest. Start on the rich end and work down until you don't notice any improvement. You can also experiment with the needle position. The general concensus about the pilot jet is to go with a 42, but I would lean towards a 40 for a lightly modded bike; that's just an opinion.

[Jersey450R]

What size main jet do you run in a F-16? LMAO

[plkmonster2]

Originally posted by Jersey450R
What size main jet do you run in a F-16? LMAO
lol. I jet kit is not worth the money. I had no luck with the needle it came with, never seemed to really pull through on the mid range. Is cals400ex still on here? He is a jettign guru! Most liekly, an exhuast/filter combo takes a 152 or 155 main. I would swap the 38 pilot out for a 42 when you can. It helps it from popping on deceleration.

[F-16Guy]

Originally posted by Jersey450R
What size main jet do you run in a F-16? LMAO
My brother got me the K&N Power Up kit with the Dyno Jet kit, so I'm running those jets. Right now, with my mods, I'm running a DJ 160. The numbers are different from the Kehin; with just a slip-on and filter, I was running a DJ 142. The different taper on the DJ needle may yield a little more power/throttle response, but not $50 worth.