Question about 1981 Yamaha XJ 650

1 Answer

I have a yamaha pw50, it runs slow when cold &

I have a yamaha pw50 it runs slow when cold & takes about half an hour to warm up & get up to speed. Does anyone know why it would run slow when cold? thanks

Posted by Anonymous on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Guru:

    An expert who has written 7 tips or uploaded 3 video tips

  • Expert
  • 267 Answers

Most likely a combination of sparkplug heat range (type of plug) and jetting, needle or air mixture settings in the carburetor. Assuming good condition of air filter and operation of the choke plunger. Are you using the correct octane fuel and fuel/oil ratio? Give the plug a clean and emery the spark contacts, set gap at 0.7mm., ideally take the plug to a Yammy dealer and check for correct range for your bike in the area where you ride.
Best to have a range of spare clean plugs handy for wet or hot days etc.
The jetting maybe dirty or wrong size too. In the meantime move the throttle needle clip down one notch. Refer to the site below for a diagram of the carburetor parts. Cheers.
http://www.cmsnl.com/yamaha-pw50r-2003_model11163/partslist/A-09.html

Posted on May 11, 2010

1 Suggested Answer

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

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Wiring diagram for pw50 yamaha


Hi, Dannie 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 $10 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.
Yamaha PW50 Wiring Diagram Troubleshoot electrical issues
PW50 WIRING DIAGRAMS
YAMAHA PW50 Owner Manual
OEM parts for Yamaha
Yamaha PW50 2000 2005 manual collection Download Manuals Technical

May 18, 2014 | 2004 Yamaha PW 50

1 Answer

Yamaha PW50 does not run clean after half throttle, how do fix


Hi, Anonymous if you have changed your fuel delivery system, air filter size or flow rate, mufflers or exhaust system or a significant change in altitude your carburetors need re-tuning and 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.
Dirt Rider Magazine
Yamaha pw50 wont run Please help Yamaha 2 Stroke
Yamaha PW50 2000 2005 manual collection Download Manuals Technical
OEM parts for Yamaha
Yamaha PW50Y Owner Manual

Nov 12, 2013 | 2008 Yamaha PW50

1 Answer

How do you take apart Yamaha pw50 shocks


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 $10 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.
PW 50 Forks PW50 Forum
pw50 fork rebuild with my 6yr old pt 1
Yamaha PW50Y Owner Manual
OEM parts for Yamaha
Yamaha PW50 2000 2005 manual collection Download Manuals Technical

Sep 28, 2013 | 2004 Yamaha PW 50

1 Answer

Pw50 fires but won't stay running


Hi, Jj9871 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 blue links below. Good luck and have a wonderful day.
pw50 won start please help
My Son Has Yamaha Pw50 That Will Start But Won Stay Runn
https://books.google.com/books?id=ozV8-Aer4N8C&pg=PA84&dq=pw50+manual&hl=en&ei=TCS2TcbdJ4PW0QG0z9jmDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CGUQ6AEwAA#v=onepage&q=pw50%20manual&f=false
OEM parts for Yamaha
Yamaha PW50 Owner Manual

Apr 14, 2012 | 2004 Yamaha PW 50

1 Answer

Pw50 throttle cable routing


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 blue links below. Good luck and have a wonderful day.
Pw50 throttle cable routing Google Search
Yamaha PW50 throttle cable replacement
https://books.google.com/books?id=ozV8-Aer4N8C&pg=PA84&dq=pw50+manual&hl=en&ei=TCS2TcbdJ4PW0QG0z9jmDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CGUQ6AEwAA#v=onepage&q=pw50%20manual&f=false
OEM parts for Yamaha
Yamaha PW50 Owner Manual

Apr 09, 2012 | 2004 Yamaha PW 50

1 Answer

How do i tune the carby on a peewee 50? the bike wont run properly


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 blue links below. Good luck and have a wonderful day.
Yamaha PW 50 checking carb
Life On 2 Wheels
https://books.google.com/books?id=ozV8-Aer4N8C&pg=PA84&dq=pw50+manual&hl=en&ei=TCS2TcbdJ4PW0QG0z9jmDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CGUQ6AEwAA#v=onepage&q=pw50%20manual&f=false
OEM parts for Yamaha
Yamaha PW50 Owner Manual

Apr 09, 2012 | Yamaha PW 50 Motorcycles

1 Answer

Yamaha PW50 stalls when throttle applied


Hi, Rick 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. Vacuum line from the petcock to intake manifold cracked.
5. Float needle and seat sticking.
6. Float level too low.
7. Carburetor bowl vent line clogged/blocked/pinched.
8. Idle adjusting screw set too low.
9. Air/fuel mixture screw set too lean.
10. Idle port, transfer ports, slow air jet clogged.
11. Slow fuel jet clogged.
12. Faulty fuel pump.
For more information about your issue and valuable "Free" downloads that you will need please Click on the blue links below. Good luck and have a wonderful day.
pw50 bogging down
PW50 won rev lots of things tried
https://books.google.com/books?id=ozV8-Aer4N8C&pg=PA84&dq=pw50+manual&hl=en&ei=TCS2TcbdJ4PW0QG0z9jmDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CGUQ6AEwAA#v=onepage&q=pw50%20manual&f=false
OEM parts for Yamaha
Yamaha PW50 Owner Manual

May 27, 2017 | 2005 Yamaha PW 50

1 Answer

How do you remove the rear tire from a yamaha pw50 dirtbike?


Hi, Boracho22 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 blue links below. Good luck and have a wonderful day.
Pw 50 rear brake yamaha rear wheel removal taking off pw50 SuperForty
PW50 Rear Wheel Change
https://books.google.com/books?id=ozV8-Aer4N8C&pg=PA84&dq=pw50+manual&hl=en&ei=TCS2TcbdJ4PW0QG0z9jmDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CGUQ6AEwAA#v=onepage&q=pw50%20manual&f=false
OEM parts for Yamaha
Yamaha PW50Y Owner Manual

Feb 21, 2012 | 2005 Yamaha PW 50

Not finding what you are looking for?
1981 Yamaha XJ 650 Logo

477 people viewed this question

Ask a Question

Usually answered in minutes!

Top Yamaha Experts

dhnguyen

Level 2 Expert

281 Answers

Steve Sweetleaf
Steve Sweetleaf

Level 3 Expert

1144 Answers

Tony

Level 3 Expert

2600 Answers

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

Answer questions

Manuals & User Guides

Loading...