Ignition problems

Marksxs650

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Hey I'm new to this cite also mechanics and I have a big problem. My XS650 is not running great it is backfiring out of the left exhaust it runs rough, it fouls plugs within a week, and it gets worse every time i change the plugs. i tired to fix the ignition timing with a timing light and its still not working. I'm at a loss right now does anyone have an idea as to what is going on?
 
I'm guessing you have points ignition. If you have two ignition coils switch the coils and see if the bad side changes to the right. I'd suspect a weak coil first.
 
Ok, not as familiar with that as some here, but would still suspect a weak coil first. They sometimes develop high voltage shorts instead of just quitting and the result is what you describe. You can measure the coil with an ohmmeter and if it reads bad it's bad, but if it reads good it could still be bad because the meter tests using low voltage
 
If it has two, just exchange the spark plug wires, leaving them on the coils, no other changes. If the problem doesn't go to the right, test compression on the left, The rule of thumb is good compression should blow your thumb off of the spark plug hole :)
 
The Pamco is designed to work with a single coil, a dual output one (2 plug wires). If the coil you have tests bad, a cheap, dependable replacement is a used Honda MP08 coil, about $10 - $20 on eBay.
 
My XS650 is not running great it is backfiring out of the left exhaust it runs rough, it fouls plugs within a week, and it gets worse every time i change the plugs.
You titled this Ignition problems, but based on that description I'd suspect the left carb.
Is the right cylinder running OK?
 
The right cylinder seems to be at a steady pace while the left is weird also the carbs should be fine I had a guy who has been working on bikes for a long time help me work on them he said the are fine but we also did a full clean of the carbs just in case. Also I was thinking this was ignition from what I’ve researched it would make sense for it to be. I could be wrong tho, I would not be surprised.
 
So I tried to do the test u told me where I switch the spark plug wires and nothing changed. The right is firing ok felt a little funny but went ok, while the left still backfired.
 
So I tried to do the test u told me where I switch the spark plug wires and nothing changed. The right is firing ok felt a little funny but went ok, while the left still backfired.
Since you have only a single coil, like 5T said, there's no point to switching wires since both plugs connect together inside the coil. ALSO -- for that reason since the cylinders are so different it points away from the coil being the main problem. If you'd bet your house the carbs are perfect then I'd look at compression on the left with a compression tester. It's hard to say the carbs are good unless everything is working right. I mean a carb can look perfect but never run right because there's immovable crud in it somewhere
 
edited
do look at that left carb, eh?
 
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One cause of a mis-behaving cylinder is an oily or fouled plug.
Analyzing the plug may help point at the cause of the mis-fires.
 
Repeat; check compression, have valves been set?
A crud compression check is the kick starter; kick through one cylinder at a time. bring it up on compression then a "moderate" kick down, are they both about equal or does one cylinder kick through "too easy" IE one hard kick, then one kicks through easy, hard kick. repeat a few times, getting a feel for it.. With good compression a cylinder will do pretty good at stopping the kick lever from dropping under just your (average guy LOL) weight.
 
I agree with the others that it sounds like a carb issue. Check your float level, and carb synchronization, and low speed air screws.
 
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