carb adjustment

[jessiewigg]

1985 suzuki dt115hp<br /><br />is there a maximum number of turns to back out the adjustment screw on the front of the carbs? dont want tho go to far and make it to lean. carbs are clean and motor runs alright. just trying to get it better. new to this site and trying to learn a few things.

 

[lonewolf5347]

Re: carb adjustment

BACKING OUT ADJUSTMENT SCREW TO FAR WILL MAKE IT RICHER NOT LEAN.THE BEST WAY I FOUND TO ADJUST LOW SPEED IDLE SCREW ARE TO INCREASE IDLE SPEED TO AROUND 950RPM TURN LOW SPEED JET SCREWS CLOCKWISE UNTIL ENGINE START TO LOOSE RPM,THEN START TURNING SCREWS COUNTERCLOCKWISE UNTIL HIGHEST RPM IS REACHED THEN A 1/8 MORE A LITTLE RICH IS FAR BETTER THAN LEAN.

 

[jessiewigg]

Re: carb adjustment

thanks for the reply and info.

 

[jim dozier]

Re: carb adjustment

Depends on the engine and carb. My Suzuki DT85 leans out when you back out (unscrew) the idle mixture screw. It bleeds in more air not more fuel. Check to see if there is a note or arrow on the airbox by the idle mixture screws. Some engines/carbs are the other way around and meter fuel not air. Get a manual, absolute necessity.

 

[jessiewigg]

Re: carb adjustment

thanks for all the replies. my dt115 motor also leans out when you back out the idle mixture screw. i was wondering is there a initial setting and a maximum number of turns it can be backed out without causing any damage from a lean condition. i have a manual but it does not cover these settings. i have the four inline mikuni carbs.

 

[jim dozier]

Re: carb adjustment

Yes it does. My manual has a table in it and I will check for you tonite. I didn't know your year when I was looking at it. It varies from year to year.

 

[jessiewigg]

Re: carb adjustment

Appreciate the help. mine is a 1985 dt115hp suzuki. inline 4 cylinder with the mikuni carbs. my manual might be different or i may have missed it.

 

[jim dozier]

Re: carb adjustment

Jessie 1985 DT115 idle air screw 1.5 turns out from lightly seated.

 

[jessiewigg]

Re: carb adjustment

thanks for all the help. i will set them on Friday and give it a run.