HELP I'm an idiot... ( with mechanical skills ).( sorta)

[KeithTurk]

Hey guys... I'm trying to wake up a 1981 XS650.. the bike has 3700 miles on it and is generally pretty good.... What I've got so far is power to the ignition ( just tested the voltage at in the left hand lower cover area.

But I have no spark... Kill switch is in the neutral position

I'm trying to get this thing running to take it to my step son in Virginia beach next weekend.... whew....

Oh and I have another one that does run sitting right beside it for parts....

 

[KeithTurk]

any thoughts?
( I have looked through the Archieves for this and most of it was to general )

I have voltage at the coil as well

 

[Airwolfie]

Give it some time dude. Not all of us hang out here 24/7. Wait at least a couple of hours for a response.

A lot of information in the tech section, have a look there.

Oh and welcome!

 

[KeithTurk]

I have Spark weak.... but spark all the same

carbs are getting re-built as we speak..

 

[Airwolfie]

Also, we do not know ANYTHING about your bike. Some info on year, model, any mods etc, you should add to your signature or in this thread at least.

 

[Airwolfie]

Sounds like a charging issue or fouled plugs. Do you have a New or old battery? Original charging system? Points or electric ignition?

 

[5twins]

The bike is 32 years old so it may not be as good as it looks from the outside. A common problem with old bikes is low voltage to the coils which results in a weak spark. All the connections and switches between the battery and coil could be a bit dirty and corroded which added up, reduces the voltage getting through. Turn the key on and test the voltage at the battery. You should see about 12, maybe a bit less or more. Now test it at the red or red/white wire that feeds the coil. It should be near the same, maybe a few tenths of a volt less. If it's a volt or two down, you've got problems.

It could also be the connections between the spark plug caps and plug wires. They get corroded or sometimes come loose. Remove the caps, cut 1/4" or so off the wires, and re-install the caps so you're tapping into some fresh wire.

 

[xjwmx]

It's very possible you have a weak coil that will never make a good spark, even if it measures good with an ohmmeter. I would suggest substituting the coil (with plug wires to make it easy) from the running bike to see what happens. Quick swap. Clean and grease the kill switch innards since power to the coil comes from there.

 

[XSLeo]

Ok, xjwmx made a good suggestion. That is if both bikes are 80 up bikes. If the other bike is a 79 or earlier it has points and the coils won't swap.
Leo

 

[crescendo]

You seems to be good at engineering. So stop calling an idiot yourself.