Hey everyone, just purchased my 1983 Yamaha XS650 and it just won’t idle. Turn it on and need to give it some throttle to get it going but immediately dies after the revs come back down. Tried adjusting the idle screw but doesn’t seem to be doing anything. Novice here so need some help. Thx
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83 Yamaha XS650 won’t idle
- Thread starter Chrismira
- Start date
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- Tags
- yamaha 650 society
Little history on the bike? A couple pics, over all, and close up of the carbs?
Cuz we don't know yet, is it pristine, stone stock, fresh out of a barn, or a hightly modified chopper?
What ignition?
Have valves been set,
cam chain tension,
compression test,
Any recent carb work done?
Fresh gas.
Have you checked voltage while running, IE is it charging?
Remove, ground, both spark plugs, crank it, strong spark?
Timing checked?
Welcome aboard.
If you're willing to do the work, AND tell us what you have and haven't done, we're willing to help.
One of many excellent self help articles found in the tech section. https://www.xs650.com/threads/bike-wont-start-running-rough.390/
Cuz we don't know yet, is it pristine, stone stock, fresh out of a barn, or a hightly modified chopper?
What ignition?
Have valves been set,
cam chain tension,
compression test,
Any recent carb work done?
Fresh gas.
Have you checked voltage while running, IE is it charging?
Remove, ground, both spark plugs, crank it, strong spark?
Timing checked?
Welcome aboard.
If you're willing to do the work, AND tell us what you have and haven't done, we're willing to help.
One of many excellent self help articles found in the tech section. https://www.xs650.com/threads/bike-wont-start-running-rough.390/
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Welcome! In addition to Gary's queries....
Often these old bikes have been sitting for some period of time. Given the symptom, the first order of business is to determine if it is running on both cylinders. Start it up and keep it running for for a bit (perhaps 15 sec) then check the temperature of each exhaust header: method 1) use an infrared thermometer, method 2) quickly touch a dampened rag and listen for somewhat equal "hiss" indicating both pipes got hot.
Can ya post pics of your machine with extra attention to top carb area?
Often these old bikes have been sitting for some period of time. Given the symptom, the first order of business is to determine if it is running on both cylinders. Start it up and keep it running for for a bit (perhaps 15 sec) then check the temperature of each exhaust header: method 1) use an infrared thermometer, method 2) quickly touch a dampened rag and listen for somewhat equal "hiss" indicating both pipes got hot.
Can ya post pics of your machine with extra attention to top carb area?
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Good pics, nice stock bike! Unfortunately, one of the things I was looking for is the fuel adjustment screws and whether they were still capped from factory. Can't see as its blocked by choke mechanism and plug wire in pic.
Where you able to start-up and assess header pipe temp.?
This is what I'm looking for @red arrow:
Where you able to start-up and assess header pipe temp.?
This is what I'm looking for @red arrow:
Great pics and looks like you have a VERY nice survivor there!
With a bit of careful cleaning and polishing that will be outstanding!
So looks like maint 101 for you,
Take a look at the plugs. Check WHAT sparkplugs are in it. Wrong spark plugs are VERY common and can cause running issues.
Looks like some replacements have been done on ignition, plug caps, wires? Which is kind of interesting cuz the wires were permanently attached to the coil on this model.
Are you willing to do some meticulous cleaning, repair?
Carbs Look untouched.
Odds are it's time for a thorough carb clean, overhaul.
That's not a job for someone who doesn't have a bit of wrench time on his resume.
What are your intentions?
With a bit of careful cleaning and polishing that will be outstanding!
So looks like maint 101 for you,
Take a look at the plugs. Check WHAT sparkplugs are in it. Wrong spark plugs are VERY common and can cause running issues.
Looks like some replacements have been done on ignition, plug caps, wires? Which is kind of interesting cuz the wires were permanently attached to the coil on this model.
Are you willing to do some meticulous cleaning, repair?
Carbs Look untouched.
Odds are it's time for a thorough carb clean, overhaul.
That's not a job for someone who doesn't have a bit of wrench time on his resume.
What are your intentions?
From the factory the idle mixture screws on US bikes are covered with brass plugs. Not sure if this applied to Canadian bikes.
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@jpdevol bike at the moment won’t run without choke on full. The previous owner did say he did work on the bike but didn’t go into detail so I can’t be of help there. Regarding the spark plugs, what should I be looking for if they are intact the wrong ones?
My father works on cars so we might be able to do the work ourselves but if it gets a little too complex might find a bike shop near me and bring it in.
Sorry for image quality, tried my best but stuff in the way
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I'll be blunt. (who me?
)
You are at a crossroads.
From scant information. Bike is sharing a space with your car in a parking garage? Care and feeding of +40 year old motorcycles is a BIG job. It will not be a reliable ride with 15 minutes of tinkering with a screw driver now and then. Is this the right bike for YOU?
Thing is as it sets, serious enthusiasts would be thrilled to dig into a bike like this and create a beautiful restoration/rider. But odds are unless you have extensive experience tools workplace that won't be happening for this year's riding season.
Here's the blunt part: Any disassembly, "fix'n" by inexpert hands will lessen it's value to those type of buyers.
So you are poised at the edge of a cliff with a big drop, is this for you?
I've been through this many times. My starting point is usually a partially disassembled bike someone gave up on...
This one is currently in my garage, bought a year after the owner got a Craigslist bargain then realized it was more work than he could get done.
)You are at a crossroads.
From scant information. Bike is sharing a space with your car in a parking garage? Care and feeding of +40 year old motorcycles is a BIG job. It will not be a reliable ride with 15 minutes of tinkering with a screw driver now and then. Is this the right bike for YOU?
Thing is as it sets, serious enthusiasts would be thrilled to dig into a bike like this and create a beautiful restoration/rider. But odds are unless you have extensive experience tools workplace that won't be happening for this year's riding season.
Here's the blunt part: Any disassembly, "fix'n" by inexpert hands will lessen it's value to those type of buyers.
So you are poised at the edge of a cliff with a big drop, is this for you?
I've been through this many times. My starting point is usually a partially disassembled bike someone gave up on...
This one is currently in my garage, bought a year after the owner got a Craigslist bargain then realized it was more work than he could get done.
Attachments
I've read a few blog posts that recommend doing this as well, thx
The brass plugs are still in. The carbs need to be off the bike to get them out.
Pretty much the carbs WILL need to come out. anything else will be unlikely to result in a bike that runs WELL.
At the very least all the old gas needs to come out, the float bowls drained, fresh gas run in and flushed for a bit.
Blunt again; There are 4 separate items requiring the carbs to come off to get the bike right.
Spark plugs: the correct plug is the NGK BP7ES if those plug caps are still the 5K resistor type.
thanks for the help. I will see what can be done and worse case bring it to a mechanic to properly do the work
To Gary’s point, I not too long ago bought a 1983 XS650SK for $50. The owner bodged it to the point that it’s useful only as parts to me. Very useful parts I might add.
Bike is in amazing shape as you can see from pics. Just need to get this work done to run smoothly.
There is a cottage industry of mechanics who repair old bikes. A Yamaha shop will send you packing. The former may require a large deposit as some repairs cost more than the value of the motorcycle.
