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real quick pilot help

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Old 05-27-2010 | 04:21 PM
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real quick pilot help

im feeling saucy and i think i may swap out my 45's to the 48's i have sitting in my garage. as im very green to carbs i played the search game on here and read around in my shop manual and just wanted to clarify some things. now i may be on with my assumptions or i may be way out in left field. the pilot jets im changing, are they the same thing as the fuel screw? or do i have to remove the fuel screw to get to these? the last carb i had apart was for my atv and i cant remember much of anything from it. also i was told that the pilot would only affect my idle and nothing else. and then i read that itll affect lower rpm operations aswell, so whos right? ill keep playing the search game on here as id like to tackle this tonite and see if i can clean up the way the bike runs a little before the weekend, or with any luck, mess it up completely, lol
Old 05-27-2010 | 04:26 PM
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found my answer, gotta yank the float bowls off i believe it says in the article on here. that being said, if i change the pilot to a 48 from a 45 do i have to adjust the fuel screws at all? i found at full throttle the bike seems fine its just when i close the throttle it pops and leans out, so would another 1/4 turn on each help with this issue?
Old 05-27-2010 | 04:28 PM
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You need to remove the float bowl to get to the pilot jet, it will be next to the main jet. The fuel screw is used to adjust the flow of the jet but has nothing to do with removing the jet.

The pilot jet is what the bike runs on until the slides start to lift which is around 2.5 -3K rpm and even then it does keep flowing as it doesn't turn off.
So it will have a slight effect on the entire RPM range.
Old 05-27-2010 | 04:33 PM
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Idle and low RPM are both affected...

Here's a picture from the manual, showing what goes where...
Attached Thumbnails real quick pilot help-jets.jpg  
Old 05-27-2010 | 04:36 PM
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You need to adjust the fuel screws about anytime you change something in the carbs... Might not need a big adjustment, but once you got it all together again, do the syncronisation & idle drop and it should be good enough...
Old 05-27-2010 | 05:11 PM
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alright thanks for the help guys
Old 05-27-2010 | 05:57 PM
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Doesn't the idle jet have it's own port in the throat of the carb?
If i'm not mistaken the idle port and pilot are parallel circuits. I think the idle port is just barely in front of the closed throttle plate, so that it works at idle, due to the high air velocity at that point. Once the throttle plate starts to open, the pilot port gets enough air velocity to ramp up. The main jet and needle (which varies the main jet opening) are also a parallel circuit.

But I could be wrong...
Old 05-27-2010 | 09:40 PM
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Uchi - if you put in the 48 PJs, start with the pilot screws out 1.5 turns. That may be close.

While you are in there, see what the main jets are and where your needle clips are for future reference. I see that you have a DJ kit installed - is there a 3rd hole in the bottom of the slide? Measure your spring length too - just to make sure.
Old 05-28-2010 | 02:12 PM
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sorry guys my a.d.d kicked in last night and i ended up going riding instead and lost interest in taking her apart. i know my needle has been shimmed and my tps is still off a bit, im gonna try to get into it tomorrow to get it closer to where it should be and i think im gonna leave the jetting to my mechanic buddy. its like brakes for me, i dont like messing with it. i was feeling good about it last night but once the motivation left me i came to the conclusion that ill mess it up and end up with a bike that runs like complete crap and not just ok. thanks for the help with this guys
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