need tips on adjusting carbs on 1989 suzuki dt85..please help!

luseguse

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can anyone give me some tips on adjusting carbs on a 89' suzuki dt85. need some ideas please help!thanx
 

jim dozier

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

I don't have my manual in front of me but my memory of reading it (Clymer manual DT85 Suzuki) was that they gave pretty specific instructions. If you don't have a manual you need one. All the experience in the world won't make up for the lack of one. There are a specific number of turns from stop for the idle jets (3 carbs) and methods for synchronization and ignition timing sychronization. When I get home I will try and post them.
 

luseguse

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

thanx jimd i would appreciate the help if u could post those notes for me .. thanx again
 

jim dozier

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

From Clymer Suzuki manual - Idle air screw adjustment turns out from lightly seated position (for idle mixture)<br />1985-1986 1-1.5 turns<br />1987 1.75-2.25 turns<br />1988-1991 1 5/8-2 1/8 turns<br />(my book only goes to 1991)<br /><br />Float setting - upside down from bottom of float to bottom of carburetor<br />1985-1986 0.69-0.77 in<br />1987-1991 0.67-0.75 in<br />Float should be approximatel level with float bowl mating surface after adjustment<br />Bend tab to adjust DO NOT press on float (will damage needle seat)<br /><br />Engine idle speed is adjusted with low speed ignition timing not throttle adjustment.<br /><br />Carburetor balancing is supposed to be done with a little Suzuki gizmo with tubes and floating balls but I would think that if the throttle plates all close together and all open completely together you're close. <br /><br />Hope this helps
 

luseguse

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

jimd, thanx alot very helpful, is the adjustment going to be different for each of the three carbs or all the same. thanx again!
 

jim dozier

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

In a perfect world all three carburetor idle air screws would start from the same position. When they tap these holes they don't necessarily start from the same place. So 1.5 turns out from the bottom may look a little different in the angle of the screw slots but you should start with them all 3 screwed out the same number of turns I would think. Then if there is some evidence of a need to change a cylinder you could tweak one but I wouldn't think you'd have any information that would tell you to do that. So they should probably all be screwed out the same.
 

luseguse

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

what about the air/fuel adjustments? any clue im at a loss.. i did the idle screws now i need to do the air/fuel adjustments..thanxs..the screws that you adjust through the spark arrestor ports.thanx again for your time and patience.
 

jim dozier

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

The idle air screws that I posted the number of turns out from the seated (screwed in) position from the manual are located beneath a removable rubber gromet (1 for each of the 3 carburetors) in the black plastic air box that covers the mouths of the carburetors. You need a long shaft narrow flat blade to reach the screws throught the gromet holes. The only other adjustment I'm aware of on the carburetor is the float bowl height (done with the carb apart) and the throttle stops which you probably don't need to mess with. Throttle, choke linkages, float assembly, and idle air screws described above are the adjustable parts, all the other jets are fixed and not adjustable just cleanable. Hope this helps. A manual is a necessity.
 

luseguse

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

thanx again, i took the boat out today and i think the fuel pumps messing up, wont stay runnin. but if u squeeze the primer bulb its ok.<br />we even take the hose off of the fuel pump and can watch it pump gas, so im at a loss. im goin to take the fuel pump apart tomorrow and ill let you know..thanx again for the advice!
 

jim dozier

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Re: need tips on adjusting carbs on 1989 suzuki dt85..please help!

Others may weigh in with some advice here but if pumping the bulb helps it is probably either the fuel pump as you suspect or an air leak between the fuel pump and the fuel tank pickup. Good luck
 
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