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Discussion Starter · #1 ·
When you switch to smaller pilots such as from 50s to 45s how much should you turn in the air screws from the recommended setting (which is 4 1/2 turns out)?

I was also wondering if performance mods such as pipes, porting and V-force reeds normally require a change to the air screw settng?
 

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Discussion Starter · #2 ·
XcellR8 said:
When you switch to smaller pilots such as from 50s to 45s how much should you turn in the air screws from the recommended setting (which is 4 1/2 turns out)?

I was also wondering if performance mods such as pipes, porting and V-force reeds normally require a change to the air screw settng?
[snapback]719065[/snapback]​
Anyone?
 

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When I did mine, I didn't have to touch them at all.
 

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Think of the pilot jet as the "coarse setting" and the air screw as the "fine setting" for this carb adjustment.If you increased the pilot jet because of a lean condition,run it first and adjust the air screw to what the motor is telling you.There are alot of variables that go into a carb setting,on a stock or modified motor. Run the sled in the throttle position you have adjusted,and tune from there.Testing is the only way to tune properly.Internet advise will get you close,but you have to tune the motor to it's variables.
 

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Another thing to keep in mind.Make sure you are adjusting the "air screw" and not the "fuel Screw". These have two different lean/rich adjustments.
 

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Acutally, the racked Mach Z carbs only use an air screw only.
 

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Discussion Starter · #7 ·
mtrsprt said:
When I did mine, I didn't have to touch them at all.
[snapback]719675[/snapback]​
So even with your mods you have 45 pilots in yours with the air screws 4 1/2 turns out?
 

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XcellR8 said:
mtrsprt said:
When I did mine, I didn't have to touch them at all.
[snapback]719675[/snapback]​
So even with your mods you have 45 pilots in yours with the air screws 4 1/2 turns out?
[snapback]720109[/snapback]​
It was my old Millenium. Yes, All I did was raise the needles one clip, and drop the pilots to 45's.
 

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Discussion Starter · #9 ·
Motor said:
Think of the pilot jet as the "coarse setting" and the air screw as the "fine setting" for this carb adjustment.If you increased the pilot jet because of a lean condition,run it first and adjust the air screw to what the motor is telling you.There are alot of variables that go into a carb setting,on a stock or modified motor. Run the sled in the throttle position you have adjusted,and tune from there.Testing is the only way to tune properly.Internet advise will get you close,but you have to tune the motor to it's variables.
[snapback]719754[/snapback]​
I haven't tried changing back to 50 pilots yet. I went to turn the air screws in a half turn from where they were to try that first but in my infinate wisdom decided that I should check where they were set and if they were even first. In the process of turning them in I kind of lost track of the # of turns as it was hard to see the screw while turning them and the screwdriver slipped a few times. I thought they were 3 1/2 to 4 turns out so I put them at 3 1/2 and it appeared to run good on the stand however shortly after driving away it started to foul up and within a km I fouled the center plug (plugs were always a nice tan brown before I touched it).

I tried turning the air screws out a half turn at a time until I was at 5 turns out but I couldn't seem to get the throttle response back to the way it was. I'm thinking I'm going to try the procedure that's in the race manual but was wondering how many turns to start at as you don't have a lot of time for adjustments once you fire it up as the pipes get pretty hot, pretty quick.
 

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Discussion Starter · #10 ·
mtrsprt said:
XcellR8 said:
mtrsprt said:
When I did mine, I didn't have to touch them at all.
[snapback]719675[/snapback]​
So even with your mods you have 45 pilots in yours with the air screws 4 1/2 turns out?
[snapback]720109[/snapback]​
It was my old Millenium. Yes, All I did was raise the needles one clip, and drop the pilots to 45's.
[snapback]720116[/snapback]​
To clip pos#3 or #4?
 

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#3 middle is stock. I raised the needles one clip, or in other words, I lower the clip one position.
 

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mtrsprt said:
#3 middle is stock. I raised the needles one clip, or in other words, I lower the clip one position.
[snapback]720168[/snapback]​
For a stock sled you dont want to raise the needles, it will kill your mileage big time!
Mtrsprt I know your aint stock.
 

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Discussion Starter · #13 ·
mtrsprt said:
#3 middle is stock. I raised the needles one clip, or in other words, I lower the clip one position.
[snapback]720168[/snapback]​
Because you lowered your pilots or because of your pipes or other mods (you got me curious as the previous owner never mentioned anything about rasing the needles when he switched to 45 pilots)?
 

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Discussion Starter · #14 ·
XcellR8 said:
Motor said:
Think of the pilot jet as the "coarse setting" and the air screw as the "fine setting" for this carb adjustment.If you increased the pilot jet because of a lean condition,run it first and adjust the air screw to what the motor is telling you.There are alot of variables that go into a carb setting,on a stock or modified motor. Run the sled in the throttle position you have adjusted,and tune from there.Testing is the only way to tune properly.Internet advise will get you close,but you have to tune the motor to it's variables.
[snapback]719754[/snapback]​
I haven't tried changing back to 50 pilots yet. I went to turn the air screws in a half turn from where they were to try that first but in my infinate wisdom decided that I should check where they were set and if they were even first. In the process of turning them in I kind of lost track of the # of turns as it was hard to see the screw while turning them and the screwdriver slipped a few times. I thought they were 3 1/2 to 4 turns out so I put them at 3 1/2 and it appeared to run good on the stand however shortly after driving away it started to foul up and within a km I fouled the center plug (plugs were always a nice tan brown before I touched it).

I tried turning the air screws out a half turn at a time until I was at 5 turns out but I couldn't seem to get the throttle response back to the way it was. I'm thinking I'm going to try the procedure that's in the race manual but was wondering how many turns to start at as you don't have a lot of time for adjustments once you fire it up as the pipes get pretty hot, pretty quick.
[snapback]720148[/snapback]​
Even though my sled has pipes, porting etc. should I start at the stock factory setting of 4 1/2 turns out and turn them in a 1/4 turn at a time or start at two or three turns out and turn them out further from there?
 

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Just start at 4 turns out, and 45 pilots.
 
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