code3cody
XS650 New Member
Hey all.
I picked up a new to me 1980 XS850 and am having some difficulty tracking down a tough / no start issue with it. A little background on the bike: bought it as a ''kind of'' runner. It has a new set of Mikuni RS carbs on it, which have never been run as the previous owner couldn't find a throttle cable that worked for the application. The starter button was stuck in so e-start doesn't work but I was able to start it briefly with the kick start and it did idle for a few seconds. It appears to be in fantastic shape otherwise (looks brand new still), so I picked it up for $500 and took it home.
Since bringing it home, I have adapted a throttle cable to work however I have only been able to get it to start once since. When it started, it ran fairly well. It would rev and idle relatively well although a little finicky. It was very difficult to start it from cold at that time, but once running seemed to run fine. Have not been able to get it to start since. Plugs are new and all the plug wires and caps are in good condition.
I believe I am chasing down an ignition issue as the bike will not start with ether directed in the cylinders though the spark plug hole or through the carbs.
I have visualized spark when cranking however it appears quite weak. I have measured the following with my multimeter:
Resistance at primary on coils of 3.1ohm on all 3.
Resistance at secondary #1 13.67ohm, #2 13.34ohm, #3 14.31ohm.
I am getting 0 volts going into coils 1 and 3 however 2 is getting somewhere around 7ish when the key is on but not cranking.
When cranking the bike I'm only getting 0.5-0.8 volts going into the 1 and 3 coils.
So my question is what voltage should I be getting into the coils with the key on and not cranking the bike, and why am I not seeing any voltage going into 2 out of the 3? Is this an ignition module that needs replacing? Is there a way to test the ignition module with my multimeter? If this is all normal, what is a good direction to start looking instead. I hope its okay to post this in a 650 forum, there doesn't seem to be much out there for the 850s otherwise.
Thanks for the help.
I picked up a new to me 1980 XS850 and am having some difficulty tracking down a tough / no start issue with it. A little background on the bike: bought it as a ''kind of'' runner. It has a new set of Mikuni RS carbs on it, which have never been run as the previous owner couldn't find a throttle cable that worked for the application. The starter button was stuck in so e-start doesn't work but I was able to start it briefly with the kick start and it did idle for a few seconds. It appears to be in fantastic shape otherwise (looks brand new still), so I picked it up for $500 and took it home.
Since bringing it home, I have adapted a throttle cable to work however I have only been able to get it to start once since. When it started, it ran fairly well. It would rev and idle relatively well although a little finicky. It was very difficult to start it from cold at that time, but once running seemed to run fine. Have not been able to get it to start since. Plugs are new and all the plug wires and caps are in good condition.
I believe I am chasing down an ignition issue as the bike will not start with ether directed in the cylinders though the spark plug hole or through the carbs.
I have visualized spark when cranking however it appears quite weak. I have measured the following with my multimeter:
Resistance at primary on coils of 3.1ohm on all 3.
Resistance at secondary #1 13.67ohm, #2 13.34ohm, #3 14.31ohm.
I am getting 0 volts going into coils 1 and 3 however 2 is getting somewhere around 7ish when the key is on but not cranking.
When cranking the bike I'm only getting 0.5-0.8 volts going into the 1 and 3 coils.
So my question is what voltage should I be getting into the coils with the key on and not cranking the bike, and why am I not seeing any voltage going into 2 out of the 3? Is this an ignition module that needs replacing? Is there a way to test the ignition module with my multimeter? If this is all normal, what is a good direction to start looking instead. I hope its okay to post this in a 650 forum, there doesn't seem to be much out there for the 850s otherwise.
Thanks for the help.
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