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Discussion Starter #1
So, we just finished replacing pistons/rings in 1998 Grand Touring 583 and it takes a while to warm up and is idling high (around 3000 RPM)........a couple of quick questions.

1. The large brass screw that adjusts the cylinder in the carb - is this the idle screw and if so, what is the adjustment for proper idling (how many turns)?

2. The small brass screw - is this the high speed jet and if so, what is the safe setting/adjustment for this to ensure safe operation, as I don't want to have piston/ring problems again (how many tunrs from fully in)?

Thx
HenBen
 

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Discussion Starter #2
So, we just finished replacing pistons/rings in 1998 Grand Touring 583 and it takes a while to warm up and is idling high (around 3000 RPM)........a couple of quick questions.

1. The large brass screw that adjusts the cylinder in the carb - is this the idle screw and if so, what is the adjustment for proper idling (how many turns)?

2. The small brass screw - is this the high speed jet and if so, what is the safe setting/adjustment for this to ensure safe operation, as I don't want to have piston/ring problems again (how many tunrs from fully in)?

Thx
HenBen[/b]
Can anyone help here or let me know where I can find a manual on-line............heading up north in the next couple of days and need to get this fixed before we go.

Much appreciated!
HenBen
 

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The small brass screw is your idle mixture and should be set at 2 turns out +/- 1/8 turn. The large screw on the side of the carbs is the idle speed adjustment and the base idle warm should be 1800 rpm.
 

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Discussion Starter #4
The small brass screw is your idle mixture and should be set at 2 turns out +/- 1/8 turn. The large screw on the side of the carbs is the idle speed adjustment and the base idle warm should be 1800 rpm.[/b]
So from what you are saying, we have the idle mixture setting correctly at 2 turns........now when we try and get sled idling around 1500-2000, we are not having any luck, no matter how we adjust the large brass screw.............any ideas what else could be wrong?

Thx for the great help Thumbdoctor.........learning lots from you guys.
HenBen
 

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Are you adjusting both carbs the same? you need to make sure both throttles are set the same. Really makes a differnece for idle. I use my fingers, down the carb throaght(while engine is off) and lightly press throttle, and feel if both carbs open at the exact same time. it is real tricky, but can be acheved. If it will not idle whatsoever, then you need to take the carbs apart and clean. Chances are there is some debris/varnish in the idle jets, blocking the idle fuel circut.

Has the sled been stored over summer/long periods without drainign the carbs? Varnish buulds up in a couple of months of inactivity. I allways drain my carbs when I store my sled for long periods.
 

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Are you adjusting both carbs the same? you need to make sure both throttles are set the same. Really makes a differnece for idle. I use my fingers, down the carb throaght(while engine is off) and lightly press throttle, and feel if both carbs open at the exact same time. it is real tricky, but can be acheved. If it will not idle whatsoever, then you need to take the carbs apart and clean. Chances are there is some debris/varnish in the idle jets, blocking the idle fuel circut.

Has the sled been stored over summer/long periods without drainign the carbs? Varnish buulds up in a couple of months of inactivity. I allways drain my carbs when I store my sled for long periods.[/b]
Thx for the feedback..........we already cleaned the carbs.........the sled has been stored over the summer without draining carbs, so that was one of the reasons we took carbs apart to clean. I will check to make sure both carbs are set the same, but if they are, any other suggestions on why idle sticks at around 3000 RPM, even when the sled is warm?
 

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with the airbox off I use a mirror if you cant see the inside of the carbs. and then I adjust the ajusters on top of the carb. that your cables are attached to..(without it running) You want them Synchronized (opening the same time). and the idle screws.. Id make sure that you turned them in all the way then out the same(for a starting point) like said above they need to be the same.
 

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Discussion Starter #8
with the airbox off I use a mirror if you cant see the inside of the carbs. and then I adjust the ajusters on top of the carb. that your cables are attached to..(without it running) You want them Synchronized (opening the same time). and the idle screws.. Id make sure that you turned them in all the way then out the same(for a starting point) like said above they need to be the same.[/b]
Thx guys............I will try this and let you know if this works.
 

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Make sure the throttle cables aren't pulled up too tight..If they are they won't let the slides back down in the carbs and turning the idle screws looser won't do anything since its the cables that are holding up the slides and not the screws..The adjustment is on top of the carb where the cable goes in..
 

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good point,make sure you have just a little play in the throttle,not alot but a "little" :p
 

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good point,make sure you have just a little play in the throttle,not alot but a "little" :p[/b]

Good stuff..............thx for all the helpful tips. I will be trying steps in the next day to see if I can get sled idling properly..........will let you know if successful.

Thx again
HenBen
 

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Good stuff..............thx for all the helpful tips. I will be trying steps in the next day to see if I can get sled idling properly..........will let you know if successful.

Thx again
HenBen[/b]
hey also dont forget about oil injection lever alignment once fixed good luck..........
 
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