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Discussion Starter #1

I just finished my second rejet. I found the stock pilot and mains on both carbs,, but one quad had 3 stock turns on the airmix screw, the other barely 1 turn on the airscrew.

A friend just contacted me, and said his new YFZ had a 42 pilot, but a 170 main!!

Did you count your turns, or check your stock jets sizes???

It may be sloppy quaiity control a Keihin Carbs,, or maybe tuned to pass green sticker???

DAMNFINO,, but a good debate topic.


Changing the jets on my daughters YFZ. Found the jet access cap (in my fingers) was loose, and had bugs in it..
 

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42 pilot, 152 main, and 2 1/2 turns on screw stock


Current, 70 pilot, 318 main, and 2 turns on screw
 

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I'll be looking at my Carb this weekend... See what's the stock Jets/Turns are too!! maybe work the "BUGS" out of it... :eek
 

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42 pilot 158 Main clip on #4 dont remember the turns
Same here with 2 turns on what you guys call the "air screw"
I've been calling it the "fuel screw" on my YZ250F for a few years now.
Honda calls it the "Pilot screw"

Im almost certian it controlls fuel flow and not air. ?
 

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42 Pilot, forget the main (threw that out the 1st day) Clip on #4, NOW the air screw seemed to be CLOSED???It took a screw driver and a pair of pliers on the screw driver to loosten it,,lol.maybe thats why the header was ORANGE??hehe
Jeff
 

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I had a 42 pilot(now a 48) a 170 main(left that alone), and the needle was on the 3rd spot. I moved it to the fifth. I run a uncorked stock pipe, and the airbox lid is off. Runs great. Oh and mine had 1.5 tuns, and I moved it to 2. I'll probobally go to a bigger main when I put on my HMF. :rock
 

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Correct me if I'm wrong but don't the local dealerships jet these quads during prep? I know at the dealership I always buy through they jet the quads themselves and then write the main jet size on the underside of the airbox lid with a yellow grease pencil.
 

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Originally posted by Tampa450@Dec 25 2003, 09:41 PM
42 pilot 158 Main clip on #4 dont remember the turns
Same here with 2 turns on what you guys call the "air screw"
I've been calling it the "fuel screw" on my YZ250F for a few years now.
Honda calls it the "Pilot screw"

Im almost certian it controlls fuel flow and not air. ?
I think you are talking about the fuel screw. You probably are not adjusting any air screws on the FCR.
Air screw are for the non-pumper, old skool carbs.
 

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I'm with Pahrump same stock jets. I am also now using a 70 pilot with a 318 main but 8 turns out on the fuel screw with the air box lid on. Also extra oil on my filter. I also took my muffler off and extended my head pipe to the rear of my bike. It's a little loud though, but it pulls hard wheelies in 5th gear from a dead stop. When I down shift into nuetral from 5th gear and hit the gas it stands straight up. Man, this thing is a rocket. There is NO WAY the trx450r will keep up with me. I have not owned anything this fast since my GSXR when I ported the flex capacitor. I can't give all the credit to the porting of the flex capacitor. I also had a carbon fiber sticker kit on it. Hope this helps..... :D
 

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Originally posted by Heinriken@Dec 26 2003, 09:04 PM
I'm with Pahrump same stock jets. I am also now using a 70 pilot with a 318 main but 8 turns out on the fuel screw with the air box lid on. Also extra oil on my filter. I also took my muffler off and extended my head pipe to the rear of my bike. It's a little loud though, but it pulls hard wheelies in 5th gear from a dead stop. When I down shift into nuetral from 5th gear and hit the gas it stands straight up. Man, this thing is a rocket. There is NO WAY the trx450r will keep up with me. I have not owned anything this fast since my GSXR when I ported the flex capacitor. I can't give all the credit to the porting of the flex capacitor. I also had a carbon fiber sticker kit on it. Hope this helps..... :D
:lol :lol Man ... those Flex Capacitors kick ass!!!! :rock Ive got one on my LT80 and it smokes raptors like they are standing still!!!!

oh .... Pahrump is actually running those jets ... he's drunk ;)
 

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Originally posted by Heinriken@Dec 26 2003, 09:04 PM
I'm with Pahrump same stock jets. I am also now using a 70 pilot with a 318 main but 8 turns out on the fuel screw with the air box lid on. Also extra oil on my filter. I also took my muffler off and extended my head pipe to the rear of my bike. It's a little loud though, but it pulls hard wheelies in 5th gear from a dead stop. When I down shift into nuetral from 5th gear and hit the gas it stands straight up. Man, this thing is a rocket. There is NO WAY the trx450r will keep up with me. I have not owned anything this fast since my GSXR when I ported the flex capacitor. I can't give all the credit to the porting of the flex capacitor. I also had a carbon fiber sticker kit on it. Hope this helps..... :D
Man I never thought about porting the flux capacitor.

But I am thinking about porting my brake caliper on the YFZ to be sure its not causeing drag.
 
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