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drz400 carb help big bore

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i recently installed a big bore kit on my drz400 but i cant get it running correctly, the jetting is giving me trouble and the coolant keeps overheating and going to the overflow. but i have the stock mikuni 36mm carb with a jd jetting kit and im not sure what jets to run. right now i have 150, 25 and the needle on the 3rd clip it wont rev ove 4000 and id rather get advice on what jets or what i need to do to fix it.

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if the coolant is just filling up the overflow tank(next to carb) while the bike is running, thats normal..the coolant is just expanding or some shit

but

i never actually sat there and watched how much it goes up and down,

i read on here its about 1-2inches from time of cold start to fully warm,, (i think)

Edited by 707LAKE

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I chainged the jets I have a 155 main 25 piolet and the red needle on 5th clip the richest setting. But the bike boggs down under accel and basicly stalls and im just looking for help

The main jet is correct for an open pipe, if you have a corked pipe or stock exhaust go to a 150 main jet.

Also move the needle to clip 4

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155 main jet

Blue needle ,

clip 4 (from top of needle)

25 pilot jet with stock fuel screw, 22.5 pj with extended fuel screw

2.75 turns

 

What colour is the coolant in the expansion tank,? I am concerned you may have a leaking head gasket...

Edited by Craigo 485sm
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if coolant just flow in the overfloww all the time:  headgasket is blown!

 

You can actually see bubble comming in the overflow tank from where the hose is connected.

 

Another way to know : when the bike is cold: start it up 10-20sec and give it some rev.  Open up the coolant drain screw at the bottom of the water pump.

-On a good working bike: the coolant wouldn't have heat up and no pressure in the coolant system should exist.

-If it  splash everywhere:  the head gasket is defect cause the system is pressurized in a couple sec.

 

ask me how I know  :p

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155 main jet

Blue needle ,

clip 4 (from top of needle)

25 pilot jet with stock fuel screw, 22.5 pj with extended fuel screw

2.75 turns

What colour is the coolant in the expansion tank,? I am concerned you may have a leaking head gasket...

I havent had a problem with the colant recently only a little bit goes to the overflow tank but its also pretty warm and humid here and I am going to try those settings. Thanks

The coolant is also blue thats the color I used

Edited by Zuki92

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if coolant just flow in the overfloww all the time: headgasket is blown!

You can actually see bubble comming in the overflow tank from where the hose is connected.

Another way to know : when the bike is cold: start it up 10-20sec and give it some rev. Open up the coolant drain screw at the bottom of the water pump.

-On a good working bike: the coolant wouldn't have heat up and no pressure in the coolant system should exist.

-If it splash everywhere: the head gasket is defect cause the system is pressurized in a couple sec.

ask me how I know :p

what do you mean the colant will splash everywhere? If the drain is open the coolant flowes out like a water hose

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if coolant just flow in the overfloww all the time: headgasket is blown!

You can actually see bubble comming in the overflow tank from where the hose is connected.

Another way to know : when the bike is cold: start it up 10-20sec and give it some rev. Open up the coolant drain screw at the bottom of the water pump.

-On a good working bike: the coolant wouldn't have heat up and no pressure in the coolant system should exist.

-If it splash everywhere: the head gasket is defect cause the system is pressurized in a couple sec.

ask me how I know :p

did you mean the cap on the radiator? I just started it and it ran for 10 to 15 seconds I turned it off and opend the coolant cap and it spat cold coolant everywhere

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coolant drain: it will splash under pressure as soon as you open it and then flow by gravity.

 

 

Engine was cold?

if so headgasket is blown.

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