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07 WR250F jetting help.

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2007 WR250F

mods:

grey wire mod

AIS blocked

airbox lid off

snorkle removed

yz throttle stop

quickshot 3

jd o-ring on AP arm

I Installed the JD jetting kit last night.

Jet settings:

main jet: 180

leak jet: quickshot 3. 3/4 turn out = #42 leak jet.

Needle: red needle c-clip on 3rd slot from top.

o-ring on ap arm.

pilot jet: #42

fuel screw turned out 2 turns

Problem:

After bike was warmed up idle seemed fine. I would Slowly turn the throttle and bike would stall out within 1/4 turn.

Started it again. While its was idling I turned the fuel mix screw in all the way, bike would still idle. So im thinking of trying a #38 or #40 pilot jet.

main and pilot jet are clean can see day light through them.

Question. Would the pilot jet cause it to bog out and stall with slow or fast throttle twist within the first 1/4 turn?

Edited by thaxtondill

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2007 WR250F

mods:

grey wire mod

AIS blocked

airbox lid off

snorkle removed

yz throttle stop

quickshot 3

jd o-ring on AP arm

I Installed the JD jetting kit last night.

Jet settings:

main jet: 180

leak jet: quickshot 3. 3/4 turn out = #42 leak jet.

Needle: red needle c-clip on 3rd slot from top.

o-ring on ap arm.

pilot jet: #42

fuel screw turned out 2 turns

Problem:

After bike was warmed up idle seemed fine. I would Slowly turn the throttle and bike would stall out within 1/4 turn.

Started it again. While its was idling I turned the fuel mix screw in all the way, bike would still idle. So im thinking of trying a #38 or #40 pilot jet.

main and pilot jet are clean can see day light through them.

Question. Would the pilot jet cause it to bog out and stall with slow or fast throttle twist within the first 1/4 turn?

If your bike is set to a proper idle, a slow twist simply lifts the slide and allows fuel to be metered by yhe needle. With a fast twist, fuel is squirted into the carb via the AP circuit.

Start by determining the correct pilot jet size. You are correct when you say the #PJ is too big if the engine does not cut out when the mixture screw is all the way in....but only when the idle is set at the lowest speed to keep the motor running. Try this first. Then set your idle to normal and see how it goes.

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If your bike is set to a proper idle, a slow twist simply lifts the slide and allows fuel to be metered by yhe needle. With a fast twist, fuel is squirted into the carb via the AP circuit.

Start by determining the correct pilot jet size. You are correct when you say the #PJ is too big if the engine does not cut out when the mixture screw is all the way in....but only when the idle is set at the lowest speed to keep the motor running. Try this first. Then set your idle to normal and see how it goes.

Thanks for the reply.

I had it at low idle speed. Than turned the fuel mixture screw in all the way no bogging or stalling. It seemed to idle better when fuel mixture screw was turned in all the way.

I'm wondering even if I put in a smaller #PJ what else would cause it to bog and stall out with any throttle movement. Why I ask... I'm stoping by a shop on my way home and want to pick up any other parts that might be the problem.

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Thanks for the reply.

I had it at low idle speed. Than turned the fuel mixture screw in all the way no bogging or stalling. It seemed to idle better when fuel mixture screw was turned in all the way.

I'm wondering even if I put in a smaller #PJ what else would cause it to bog and stall out with any throttle movement. Why I ask... I'm stoping by a shop on my way home and want to pick up any other parts that might be the problem.

If it was a bog whilst accelerating during normal riding, I would be looking at correct AP function. Set the pilot circuit first. Normal idle during use should be in the 1500 - 1800 rpm. A common mistake is to have the idle too low which will cause a stall no matter what jetting is installed.

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If it was a bog whilst accelerating during normal riding, I would be looking at correct AP function. Set the pilot circuit first. Normal idle during use should be in the 1500 - 1800 rpm. A common mistake is to have the idle too low which will cause a stall no matter what jetting is installed.

I didnt try riding the bike due to when ever turned the throttle fast or slow the bike dies within the first 1/8 1/4 turn. Im going to try the small PJ and go from there.

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Picked up #40 and #45 pilot jet to test out. I decided to try another rout before replacing the PJ.

I changed out the main jet from a #180 to #175. I set the fuel screw to 2 turns out. Quickshot at 1/2 turn out. The bike seems to run much better. It still has slight bog at 1/4 throttle.

After riding around for 10-15 mins. I stop and turned the fuel screw in about 1-1/2 turns the bike stalled out. Turned it out 1/4, started it and turned it out tell rpm's rises. About 1-3/4.

New jet setting:

Main jet: 175

Needle: red c-clip on 3rd slot

pilot jet: 42

leak jet: quicksot 3. 1/2 turn out

Fuel screw: 1-3/4 turns out

o-ring mod

Any Ideas how i can elminate the slight bog just about 1/4 twist on throttle?

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Jetting up date.

So i messed with the ap timing this morning.First removed the throttle cable cover on carb. Than road the bike around for ten mins to warm it up. I turned the ap screw 1/2 turn ccw. Seemed to take way a little of the bog. I turned it another 1/2 ccw turn. Bog is pretty much gone!!!

final jetting:

Main jet: 175

Needle: red c-clip on 3rd slot (thinking of going to 4th slot)

pilot jet: 42

leak jet: quicksot 3. 1/2 turn out

Fuel screw: 1-3/4 turns out

o-ring mod

I have a couple questions.

1. I noticed the black ap black cam moves very slowly. when i give it throttle. Should I remove the o-ring and use a thin wire or zip tie to speed up the black cam?

2. By moving the c-clip to the 4th slot on needle would that give me more mid throttle power?

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Jetting up date.

So i messed with the ap timing this morning.First removed the throttle cable cover on carb. Than road the bike around for ten mins to warm it up. I turned the ap screw 1/2 turn ccw. Seemed to take way a little of the bog. I turned it another 1/2 ccw turn. Bog is pretty much gone!!!

final jetting:

Main jet: 175

Needle: red c-clip on 3rd slot (thinking of going to 4th slot)

pilot jet: 42

leak jet: quicksot 3. 1/2 turn out

Fuel screw: 1-3/4 turns out

o-ring mod

I have a couple questions.

1. I noticed the black ap black cam moves very slowly. when i give it throttle. Should I remove the o-ring and use a thin wire or zip tie to speed up the black cam?

2. By moving the c-clip to the 4th slot on needle would that give me more mid throttle power?

You can lock wire them together. Watch for any binding or you will break the plastic arm.

As for the clip position.......try it and see.

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Bike sat for 6 months with gas in carb:(. Got it started and ran like poop.

Today I took the carb out cleaned all and need up changing the needle to the 4 slot. Bike started up great and runs better than ever!!

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Final jetting:

Main jet: 175

Needle: red c-clip on 4th slot

pilot jet: 42

leak jet: quicksot 3. 1/2 turn out

Fuel screw: 1-3/4 turns out

o-ring mod

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