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1985 K100 RS won't start Mon Feb 26, 2018 12:34 am
FrederikHolm
active member
Hello!
As i mentioned in my intro post, my name is Frederik and I am currently restoring my dads 1985 K100 RS.
After reassembling the bike, I had it up and running but had to turn i off again, since there was still a few bits I needed to fit.
A few days later I wanted to start it up again, and it wouldn't start.
Decided to pull the plugs to check for sparks. The four plugs all spark, all though i would have expected a more power full spark. Drained the gas tank, and put in some fresh fuel, still not starting. Pulled the plugs again, and noticed that they are soaked in gas.
Decided to remove the injector bar to check if any of the injectors where stuck in the open position, but the where not. I did notice that they spray in a very thin pattern. Don't know if they are supposed to do that, but I found this video on YouTube and it is prettys simmilar: https://www.youtube.com/watch?v=n06q8fjFR9k
I then found Bertrand Vogels guide on troubleshooting the K100; http://hrsbstaff.ednet.ns.ca/bvogel/K100/download/bike-wont-start1.htm (Great guide by the way, thanks a lot)
Since I was pretty sure the fuel was not the problem, I decided to check the ignition coils.
As the guide descibes, there should be around 12.6 kΩ between the secondary coils and 2.6 Ω between the primary coils.
Heres my measurements:
ZYL. 1 & 4: Primary = 0Ω Secondary = 0Ω
ZYL. 2 & 3: Primary = 0Ω Secondary = 9.57 kΩ
It would appear that there is a failure in the ignition coil serving the nr. 1 and nr. 4 cylinder. But how can a spark occur, at the sparkplug of both cylinder 1 & 4, if the coil is bad? As i mentioned, I have sparks at all four cylinders.
Appreciate the help!
Kind regards, Frederik.
As i mentioned in my intro post, my name is Frederik and I am currently restoring my dads 1985 K100 RS.
After reassembling the bike, I had it up and running but had to turn i off again, since there was still a few bits I needed to fit.
A few days later I wanted to start it up again, and it wouldn't start.
Decided to pull the plugs to check for sparks. The four plugs all spark, all though i would have expected a more power full spark. Drained the gas tank, and put in some fresh fuel, still not starting. Pulled the plugs again, and noticed that they are soaked in gas.
Decided to remove the injector bar to check if any of the injectors where stuck in the open position, but the where not. I did notice that they spray in a very thin pattern. Don't know if they are supposed to do that, but I found this video on YouTube and it is prettys simmilar: https://www.youtube.com/watch?v=n06q8fjFR9k
I then found Bertrand Vogels guide on troubleshooting the K100; http://hrsbstaff.ednet.ns.ca/bvogel/K100/download/bike-wont-start1.htm (Great guide by the way, thanks a lot)
Since I was pretty sure the fuel was not the problem, I decided to check the ignition coils.
As the guide descibes, there should be around 12.6 kΩ between the secondary coils and 2.6 Ω between the primary coils.
Heres my measurements:
ZYL. 1 & 4: Primary = 0Ω Secondary = 0Ω
ZYL. 2 & 3: Primary = 0Ω Secondary = 9.57 kΩ
It would appear that there is a failure in the ignition coil serving the nr. 1 and nr. 4 cylinder. But how can a spark occur, at the sparkplug of both cylinder 1 & 4, if the coil is bad? As i mentioned, I have sparks at all four cylinders.
Appreciate the help!
Kind regards, Frederik.
