Motorcycle Repair: yamaha radian yx 600 1986


Question
Hi. there is a problem...i was riding the bike all day long and at the final of the ride she simply shut off in the middle of the road. its sound like is a  electrical power......the ignition coils are new.in home i check the bike and she started like nothing happend.when I check the coils with the service manual, sometimes I got the numbers and sometimes no. when I start the motorcycle, sometimes only works 2 cylinders and sometimes it works with all four cylinders. I just got a used cdi and the problem continues.please tell me something I am getting crazy. thanks!!

Answer
Hi Marcos,

Often when you are getting intermittant problems
like that it can be frustrating.

One thing that can cause problems like that is if
you have a side stand switch or ignition switch
that is faulty. Side stand switch may ground out the ignition
if bad.

There may also be contact problems on the engine stop/run
or kill switch.
These things can be a possibility if you feel the fuel
system is okay.

The battery needs to be strong to prevent ignition
drop out and the ignition plugs or connectors
should be cleaned with electronic spray as they
become corroded after many years.

Your coils must always have power on the red/white wires
so even a bad or loose fuse or fuse connector could drop
out the power to the coils when riding.

Probably you have a loose connection on one of the above
mentioned items. Last resort after checking
these things might be to replace the ignition pulse coil(s)
or sometimes called a pickup coil.
This is under the left engine cover, should read 108-132 ohms
but they can act up when hot usually.

Try to check out one thing at a time. You may even have
a couple of things that need repair so it seems confusing
at first.

Wayne S
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