Question about Yamaha 2003 Yz450f Yz450 Yz Wr 450 Stator Stater Electric Generator Voltage Pulse Coil

1 Answer

2003 yz450f popping on deacceleration too lean

Yz450f running lean. got a 50 pilot jet and airscrew almost all the way out and its still a little too lean. shouldn't need any bigger than a 45 pilot jet. replaced intake boots/joint and got a new air/fuel screw

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Renaissance:

    An user who is expert in 3 categories / brands.

  • Yamaha Master
  • 1,190 Answers

Wots the colour of the plug after its had a good run? is the exhaust gasket on the head leaking as this can cause this ? have you coated the air filter with a film of oil as this is required and also stops dirt passing through it ? correct spark plug and gap ? timing set correctly ?

Posted on Dec 06, 2013

2 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

  • 125 Answers

SOURCE: 2003 yz450f too lean backfiring on deacceleration

clockwise is rich & cc is lean which way are you adjusting?
clean the small air port in carb with adjustment screw removed.
Screw should be set 1 1/2 turns fron light seated position.

Posted on Nov 22, 2013

Testimonial: "yes it shouldn't be anymore than two turns out. it only stops backfiring when the screw is about 4 turns out. I took the carb apart and sprayed carb cleaner through all the ports. I should only be running a 46 at the biggest with about two turns out but its not working out"

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Wont idle on its own


Hi, Anonymous and the usual suspects are:
1. Idle circuit and transfer ports clogged.
2. Air fuel mixture adjustment too lean.
3. Pilot jet clogged.
4. Faulty accelerator pump.
5. Float level too low.
6. Float bowl contaminated old fuel, water, dirt, rust, etc.
7. Float bowl vent or overflow tube clogged.
8. Fuel flow to carburetor restricted.
9. Intake manifold leak.
10. The gas cap is not venting properly or fuel tank venting system blocked.
11. Vacuum line from intake manifold to petcock broken, cracked, or not attached, carburetor vent line plugged.
12. Needle and seat stuck closed in the float bowl.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have nice a day.
2010 YZ450f starts but soon stops bike stalls FOUND ANSWER
2007 2013 Yamaha YZ450F Service Repair Workshop Manual Download Manuals...
OEM parts for Yamaha
http://mybikemanuals.com/yamaha/yamaha-yz-owners-manuals

Mar 01, 2014 | 2007 Yamaha yZ 450 F

1 Answer

2003 yz450f running too lean


First, try to avoid ethanol. It melts carb lines, and can goo up small passageways. Get some good gas and try again. Hi test if necessary. Check your specs, maybe the bike requires hi test.
Taking apart and cleaning involves soaking in fresh carb solvent to clean the small passageways. Is there an air cleaner? It may be clogged, test with it off.

Nov 22, 2013 | Motorcycles

1 Answer

2003 yz450f too lean backfiring on deacceleration


clockwise is rich & cc is lean which way are you adjusting?
clean the small air port in carb with adjustment screw removed.
Screw should be set 1 1/2 turns fron light seated position.

Nov 21, 2013 | Yamaha 2003 Yz450f Yz450 Yz Wr 450 Stator...

1 Answer

Yz450f running too lean


Hi, Anonymous if your fuel system (gas tank, filters, fuel valve and carburetor) is contaminated with ethanol sludge, varnish, rust, dirt, water etc. or your bike has been sitting for months or years without running these components must be "PROPERLY" cleaned and reassembled "CORRECTLY" before any adjustments can be made. Tuning your carburetor is fairly simple once you understand the basic principals. You engine is a simple airbox sucking air in and blowing it out, it is finely tuned at the factory for maximum performance once you upset that delicate balance by changing air filters, camshafts or exhaust systems your performance may go down the and the engine may run poorly, you need to compensate the air-fuel mixture in the carburetor in order for the engine to run smoothly and at peak performance. If you are running multi carburetors you need to sync them first and make sure your air cleaner element is clean and dry for paper elements or lightly oiled for foam and meshed elements and properly installed. Here is how and where you compensate trouble: "TIP" if your engine "BOGS" your not getting enough fuel.
1. Closed to 1/8 throttle is managed by the air screw and pilot/slow jet.
2. 1/8 to 1/4 throttle is managed by the air-screw, pilot/slow jet, and throttle slide.
3. 1/4 to 1/2 throttle is managed by the throttle slide and jet needle.
4. 1/2 to 3/4 throttle is managed by the jet needle, needle jet, main jet, and air jet.
5. 3/4 to wide open throttle is managed by the main jet and air jet.
6. Wide open throttle is managed by the main jet.
If you are running lean, spark plug electrode color is white, engine runs hot and feels like it is starving for fuel you need to go up on the jet size or move the c-clip down one notch. If you are running rich, spark plug color is black or dark gray, engine runs cool, and bogs down when accelerating you need to go down on jet size or move the c-clip up one notch. When your carburetor is properly tuned for maximum performance your spark plug electrode will be a light tan color like coffee with cream. If you prefer fuel economy over performance you can go down on main jet sizes until a satisfactory level of lower performance is acceptable versus MPH, your spark plug color will be whiter and your engine will run warmer. These tuning adjustments will only make improvements if your intake and exhaust system have no air leaks or sealing issues and the entire electrical system is in proper working order and you have no mechanical issues. For more information about your issue and valuable "FREE" downloads that you will need please click on the websites below. Good luck and have nice a day.
Too lean rich 2006 yfz 450
How To 4 Stroke MX Fuel Screw Adjustment YZF CRF KXF RMZ FCR Part 1 of 2
YAMAHA YZ450F Owner Service Manual
OEM parts for Yamaha
http://www.yamaha-motor.com/assets/service/manuals/2004/lit-11626-17-11_784.pdf

Aug 19, 2013 | Yamaha YZ 450 F Motorcycles

1 Answer

Will not idle without choke


Hi, Anonymous and the usual suspects are:
1. Fuel cap or fuel tank is not venting properly.
2. Fuel filter clogged.
3. Fuel line pinched or kinked.
4. Float needle and seat sticking.
5. Float level too low.
6. Carburetor bowl vent line clogged/blocked/pinched.
7. Idle adjusting screw set too low.
8. Air/fuel mixture screw set too lean.
9. Idle port, transfer ports, slow air jet clogged.
10. Slow fuel jet clogged.
11. Faulty fuel pump.
For more information about your issue and valuable "Free" downloads that you will need please Click on the links below. Good luck and have a nice day.
05 yz450f wont idle must run by friday YZ 400 426 450
Wont run without the choke yz450f 03
YAMAHA YZ450F Owner Service Manual
OEM parts for Yamaha
http://www.yamaha-motor.com/assets/service/manuals/2004/lit-11626-17-11_784.pdf

Jul 21, 2013 | Yamaha YZ 450 F Motorcycles

1 Answer

I have a yz450f 06 and its not running right its spluttering and poping on take off and cruizing at low throttle.


clean plugs, is the smaller jet blocked. is vacuum pipe to tank leaking anywhere.

Mar 11, 2013 | Motorcycles

1 Answer

Fork oil capacity for 2003 yz450f


Hi, Anonymous for this scenario you will need your service/owners manual if you can't find the first and best tool you ever bought for your Yamaha, despair not, for a mere zero $0 you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
2003 YZ450F Fork Oil Change
How much goes to 2004 YZ450F forks
Yamaha 2003 YZ450F Owner Service Manual
OEM parts for Yamaha
http://mybikemanuals.com/yamaha/yamaha-yz-owners-manuals

Feb 26, 2013 | 2008 Yamaha yZ450F

1 Answer

05 YZ450F wont idle just not sure how to adjust the idle?


Hi, Bryce and the usual suspects are:
1. Idle circuit and transfer ports clogged.
2. Air fuel mixture adjustment too lean.
3. Pilot jet clogged.
4. Faulty accelerator pump.
5. Float level too low.
6. Float bowl contaminated old fuel, water, dirt, rust, etc.
7. Float bowl vent or overflow tube clogged.
8. Fuel flow to carburetor restricted.
9. Intake manifold leak.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have nice a day.
04 yz450f wont idle NEED HELP
06 YZ450F Wont Idle
YAMAHA YZ450F Owner Service Manual
OEM parts for Yamaha
http://www.yamaha-motor.com/assets/service/manuals/2004/lit-11626-17-11_784.pdf

Jun 25, 2012 | 2004 Yamaha YZ 450 F

1 Answer

I was riding my 03 yz450f and it back fired and just died. then i tried to start it had a hard kick and had to use hotstart to start it once started ran 2 seconds and backfried and died. then tried...


hi mate backfire usually points to lean fuel condition but in your case being quite severe maybe blocked pilot jet. I would remove carbi and compress air clean it with pilot jet out and clean or replace pilot jet they only cost a few dollars...
I would also highly recommend a leak down test to double check your valves are sealing well and compression is all within range.
any Yamaha shop can do this test for you if you don't have the equipment, may be hundred or so but could save you heaps with accurate diagnosis in case something major is wrong??
regards Jamie

Jul 24, 2011 | 2003 Yamaha YZ 450 F

1 Answer

I have a 2004 yz450f and am having a hell of a time getting it to run right. I checked all of the resistances on the electrical system and they are good, but it doesn't seem to be getting a strong spark. ...


Hi, Spinmanbob and the usual suspects are:
1. Idle circuit and transfer ports clogged.
2. Air fuel mixture adjustment too lean.
3. Pilot jet clogged.
4. Faulty accelerator pump.
5. Float level too low.
6. Float bowl contaminated old fuel, water, dirt, rust, etc.
7. Float bowl vent or overflow tube clogged.
8. Fuel flow to carburetor restricted.
9. Intake manifold leak.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have nice a day.
Motor bogs when stab throttle
2008 yz450f bogs when throttle opens YZ 400 426 450
YAMAHA YZ450F Owner Service Manual
OEM parts for Yamaha
http://www.yamaha-motor.com/assets/service/manuals/2004/lit-11626-17-11_784.pdf

Jun 12, 2010 | 2004 Yamaha YZ 450 F

Not finding what you are looking for?
Yamaha 2003 Yz450f Yz450 Yz Wr 450 Stator Stater Electric Generator Voltage Pulse Coil Logo

103 people viewed this question

Ask a Question

Usually answered in minutes!

Top Yamaha Electrical Supplies Experts

John Trevino

Level 3 Expert

1383 Answers

Roland W VanLue
Roland W VanLue

Level 3 Expert

486 Answers

Dusty Ryan

Level 1 Expert

28 Answers

Are you a Yamaha Electrical Supply Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...