Question about 1981 Yamaha XJ 650

2 Answers

When idling engine spits back thru carbs

81 yamaha 650 xs special

Posted by on

2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 3 Answers

When was the last time you had the carbs synchronized? If they are not flowing the same it could couse this problem.

Posted on Jul 02, 2009

  • 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.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 408 Answers

You should check the valve clearances, camshafts timing and make a compression test on the engine too.
One or more of your inlet valves is/are either not closing entirely or they close but their stem is damage and it doesn't seal off the combustion chamber properly.

Posted on Jun 28, 2009

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

I have a 1980 yamaha xs 1100 special, it sat in a garage for 3 years, i replaced the fuel lines, cleaned the tank, and replaced the plugs, how come it only idles when the choke is on and it sounds like a...


You probably have varnish build up in the carburetors, causing restricted air flow, and therefore the engine is running too lean, especially on the right side, and a lean running engine will run hot at the exhaust. It only idles when the choke is on because the choke creates a richer fuel supply. A can or two of commercial fuel cleaner through the fuel supply may get the engine's jet's orifices cleaned out. Otherwise, overhaul the carbs.
Hey, nice old bike, though. Good luck

May 20, 2011 | 1979 Yamaha XS 650 F

1 Answer

1980 Yamaha XS 650 special not charging


check the rotor magnet to see if the windings are shorted to the base use an ohm meter to check for grounding to the base.

Apr 04, 2010 | 1980 Yamaha XS 650 G

2 Answers

I have an 81 yamaha 650 maxim that will only idle with the choke on


WELL ITS SOUND LIKE YOU HAVE CLOGED JET IN CARB OR CACUME LEAK AT THE CARB BOOT NEED TO CLEAN CARB IF BOOTS OK

Mar 16, 2010 | 1981 Yamaha XJ 650

1 Answer

1980 XS650 Special II. Timing acts like it has jumped. Will run but won't idle.


carb may need overhaul-take apart n put in solvent-try ajustin idle speed 1st--inspec ign wiring-the timing is controlled by a computer box-may need new-1st chec batt condition-make sure connections r tite--secure a clymer manual for details n keep in touch I had 2 of these babies

Jan 26, 2010 | 1980 Yamaha XS 650 G

1 Answer

How to take a starter off a 81 yamaha 650xs


take off the part that goes round the handle bars then take it apart and un srue the cable from the engin transformer.

Nov 01, 2009 | 1981 Yamaha XS 650 H

1 Answer

Can't find Model number.


I checked with a local Yamaha Dealership. They found it.

It's a SF model.

Aug 29, 2009 | 1979 Yamaha XS 650 F

1 Answer

80 xs 650 hesitation and exhaust "popping"


Most likely the carbs need cleaning and adjusting. You may want to richen the A/F ratio when you do it. They are set really lean from the factory. I would go 1/4-1/2 turn out on the A/F screw.

Jul 22, 2009 | 1979 Yamaha XS 650 SF

1 Answer

When warm will not stay running+leaks oil to the air cleaner


This is an XS 650, no? Sounds like you might have some piston ring blow-by (especially if its burning some oil), or possibly bad valve seal's'. The valves could be tight, so make sure the valve clearance is correct first, then compression test, and finally a 'leak-down' test.

If it is blowing by, it probably is fouling plugs and you will need more energy in the spark to fire, but this is a secondary issue, which will be eliminated with the fixing of the other issues. Good luck!

Jun 25, 2009 | 1981 Yamaha XJ 650

1 Answer

Engine idles with choke on only


You either have cracked intake boots/ manifolds or the idle circuit in the carb is plugged with stuff. Spray some brake cleaner around the intake manifolds (air box in place) and see if the idle picks up. If nothing happens pull the air box, fire it up and put your hand over the carb(s) to try to **** it through....rev it up...cover carb with hand...repeat. Next you're removing carbs and cleaning

Dec 17, 2008 | 1978 Yamaha XS 650 SE

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

Related Topics:

246 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...