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'85 K100RS won't start - need help with diagnostics please Wed Jan 11, 2017 2:52 pm
Matthew1971
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Hello K-bike gurus,
In an effort to convey all the pertinent information to you guys/gals, I may offer some seemingly irrelevant background details (like this particular statement). Just chalk it up to my inexperience in K-bike ignition diagnostics.
If you would prefer to skip the backstory altogether, just go down to the long line of asterisks. This is where I start the list of symptoms.
So, three years ago when I bought the bike, it was yellow. It was very visible, but ... yellow. I prefer, hopefully never to my detriment, a more stealthy appearance. I hesitated in painting it for a while because I had this feeling that just after it was looking the way I had envisioned, something mysterious and/or catastrophic would happen mechanically or electrically. Well, my nightmare appears to be in the act of becoming a reality. One reason for this background info is to hopefully explain why I have been operating the bike in a less than ideal (read: stupid) condition. It is also helpful to know - currently this is my only source of motorized transportation - creating the need to operate the bike in a, sometimes, vulnerable condition. Additionally, as the painting project required multiple, full un-dressings of all fairing components, I have been spurred to start all sorts of minor projects involving the elements uncovered in the process. At times I've wondered if I had essentially opened a can of worms that would not be satiated until I had replaced every one of the 30 year old parts - which is of course the entire bike.
So, on with the issue -
While the bike 'appears' to have been garage kept in the past, soon after buying it I had trouble with the keyed portion of the ignition switch - namely that I could not remove the key. The key would turn and operate the switch, but I could not remove the key. In an attempt to understand how the switch operated, I noticed that the "real switch" portion was barely holding on to the back of the keyed section. It was so easily removed and brought out from behind the dash pad that I wondered how it had not become dislodged every time I rode over a speed bump. So, until I could get some graphite lubricant and remove the key, this is how I secured the bike. I'm ashamed to admit, I continued to operate the bike in this condition for far too long.
The key remained in the bike. When I arrived at my destination, I would turn the engine off by way of the stuck key, reach behind the dash pad, and pull the switch out so that the keyed section had no contact with the switch. Due to the astonishing ease at which these two parts were separated, I became quite proficient and lightning fast performing this maneuver. I felt this was necessary for the security of my bike, just in case someone I hadn't noticed was watching me. While this may seem to be an irrelevant bit of background, I want to explain the inordinate abuse and exposure this ignition switch has endured.
More recently - after finding an adapter of nearly appropriate size, I decided to install some USB ports in the vacant slot of the dash pad. I removed the dash pad completely in order to make slight size modifications to the empty slot, fabricate a different switch blank for trim around the USB ports, and enjoy working comfortably from a plush chair under sufficient lighting in a warm room of my house. As a consequence, the ignition switch no longer had the protection from the elements offered by the dash pad. With the keyed portion of the switch removed along with the dash pad, the operation of the ignition switch was performed with my house key, which has a wide blunt end about the length of the slot in the switch. This had been the situation for the past week. I don’t recall getting much rain during that period, just a whole lot of cold. The bike is parked in a carport at my house, free from any precipitation.
Just yesterday the bike started cutting out while running, and coincidently only when driving. After the unexpected loss of power, I looked down at the gauges and noticed that all lights had gone out. I naturally grabbed the switch mechanism resting on the handlebars. As soon as I grabbed it, the connection was restored and I was able to continue with little loss of speed. The second, and all subsequent times this happened yesterday (around five times in total, maybe four), it took just a little more than grabbing the switch. A few times I had to jostle the mechanism in my hand for a second before the power was restored. There was no need to pull over and stop during any of these situations.
Then, on my way home to address this issue in the comfort of my carport, I decided to make a quick stop at the grocery store. When I went to start the bike and go home, I once again placed my house key in the switch and turned it. I hit the starter button. The engine turned over for a fraction of a second and then stopped. I noticed that the headlight and all dash lights had gone out. I wasn’t too worried; I was sure that a simple jostle of the switch in my hand was all that was needed – but it never did work like it had been. The proper dash lights were never restored (the sign I was looking for as an indication that whatever connection was faulty had been restored). A few times the proper dash lights made an attempt to illuminate fully but did not. They would occasionally illuminate, however faint. Pressing the starter button during those times effectively does nothing.
[By proper dash lights, I mean the green neutral light and all the backlighting in the cluster, as well as the clock and the LCD gear indicator]
After further attention was given to recording exactly what symptoms the bike was expressing, I noticed that when I turn the switch all the way (passed the parking light/aux position) to the on position, the battery (charge) light makes a feeble attempt to illuminate, viz. appears as if less than the required voltage is being delivered.
This is when I removed the battery and walked home with it. I put the 8-month-old battery, with which I never had the first problem, on the trickle charger overnight. This morning the green light on the charger indicating a full or near full charge state was lit as expected. I carried the battery back to the bike.
Before re-installing the battery, I used sandpaper and contact cleaner to thoroughly clean all the connectors on both grounds to the frame (the one on the transmission next to the battery, and the one under the tank on the center frame rail). The symptoms were exactly the same, no change at all.
Further experimenting has led to some, I believe, strange symptoms. With the ignition switch in the on position and the kill switch straight up, the symptoms listed previously were witnessed. With the ignition switch in the on position and the kill switch to either side (in the “kill” position), the half-lit charge light goes out and a continuous buzzing emanates from one of the smaller relay switches under the tank. Judging from a diagram I have, I believe it’s the fuel injection relay. It’s on the forward side of the relay box and the furthest one to the left hand (clutch) side of the bike – one of the three similarly sized relay switches.
Honestly, as per a friend and long time Beemer guy’s advice, I haven’t really ever used the kill switch. He’s warned that they have a reputation for failure and advised I refrain from using it. So, I’m not real sure just how the bike is expected to respond to using the kill switch with the ignition switch on. But, these symptoms just strike me as probably not intended.
So, feeling that the problem is not the battery, I tried some further diagnostics.
********************
Again, when I turn the switch all the way (passed the parking light/aux position) to the on position, the battery (charge) light makes a feeble attempt to illuminate, viz. appears as if less than the required voltage is being delivered. All other instrument cluster lights (and both LCD units - clock and gear indicator), including the headlight, turn signals, brake light and horn do not operate when the switch is turned to the on position. And, of course the starter will not turn – no solenoid click – nothing.
With the ignition switch in the on position and the kill switch to either side (in the “kill” position), the half-lit charge light goes out and a continuous buzzing emanates from one of the smaller relay switches under the tank. Judging from a diagram I have, I believe it’s the fuel injection relay.
With the ignition key in the ‘off’ position – the red wire on the ignition switch has about 12.6 – 12.7 volts and the green wire has 0 volts.
With the ignition key in the ‘on’ position, and again not the parking light/aux position but the ‘on’ position – the red wire now has 2.34 volts! A very significant voltage drop. And the green wire registers a similar voltage.
This strikes me as unusual and completely WRONG!
I think I’ve conveyed all the symptoms that I have noticed or know to check for.
I’ve read some posts about measuring the voltage from the fuse panel but I’m not clear on what is expected and where. Additionally, I’m assuming that to properly measure at the fuse panel, I would place a probe on one side of the particular fuse slot (and only one particular side should register - because when you pull the fuse you break the circuit) and the other probe to ground on the frame. Is this correct?
Does anyone know of a good reference for what to expect at each fuse slot, and under what circumstances (key on or off)?
In my search of the Internet for anything that might shed some light on my problem and help with the diagnostics, I kept coming across Bertrand Vogel’s EFI/Electronic ignition K100 2v troubleshooting.
http://tomwade.me/motorcycles/technical/k100troubleshooting.pdf
While this is undoubtedly invaluable information every relevant K-bike owner should have, I believe I need help in the diagnostics that he mentions should be performed BEFORE consulting his troubleshooting guide. He starts his guide with this preface:
First, you have done all the basic troubleshooting such as: checking the fuses, ignition switch, kill switch, side stand switch (not applicable on early K100), transmission in neutral, clutch in, starter connection, Fuel pump connector on the fuel tank, and battery connections.
I believe I should start with these sorts of tests, in particular the ignition and kill switch troubleshooting. Does anyone know of a comparable guide that addresses these preliminary measures?
Thanks in advance for any assistance.
In an effort to convey all the pertinent information to you guys/gals, I may offer some seemingly irrelevant background details (like this particular statement). Just chalk it up to my inexperience in K-bike ignition diagnostics.
If you would prefer to skip the backstory altogether, just go down to the long line of asterisks. This is where I start the list of symptoms.
So, three years ago when I bought the bike, it was yellow. It was very visible, but ... yellow. I prefer, hopefully never to my detriment, a more stealthy appearance. I hesitated in painting it for a while because I had this feeling that just after it was looking the way I had envisioned, something mysterious and/or catastrophic would happen mechanically or electrically. Well, my nightmare appears to be in the act of becoming a reality. One reason for this background info is to hopefully explain why I have been operating the bike in a less than ideal (read: stupid) condition. It is also helpful to know - currently this is my only source of motorized transportation - creating the need to operate the bike in a, sometimes, vulnerable condition. Additionally, as the painting project required multiple, full un-dressings of all fairing components, I have been spurred to start all sorts of minor projects involving the elements uncovered in the process. At times I've wondered if I had essentially opened a can of worms that would not be satiated until I had replaced every one of the 30 year old parts - which is of course the entire bike.
So, on with the issue -
While the bike 'appears' to have been garage kept in the past, soon after buying it I had trouble with the keyed portion of the ignition switch - namely that I could not remove the key. The key would turn and operate the switch, but I could not remove the key. In an attempt to understand how the switch operated, I noticed that the "real switch" portion was barely holding on to the back of the keyed section. It was so easily removed and brought out from behind the dash pad that I wondered how it had not become dislodged every time I rode over a speed bump. So, until I could get some graphite lubricant and remove the key, this is how I secured the bike. I'm ashamed to admit, I continued to operate the bike in this condition for far too long.
The key remained in the bike. When I arrived at my destination, I would turn the engine off by way of the stuck key, reach behind the dash pad, and pull the switch out so that the keyed section had no contact with the switch. Due to the astonishing ease at which these two parts were separated, I became quite proficient and lightning fast performing this maneuver. I felt this was necessary for the security of my bike, just in case someone I hadn't noticed was watching me. While this may seem to be an irrelevant bit of background, I want to explain the inordinate abuse and exposure this ignition switch has endured.
More recently - after finding an adapter of nearly appropriate size, I decided to install some USB ports in the vacant slot of the dash pad. I removed the dash pad completely in order to make slight size modifications to the empty slot, fabricate a different switch blank for trim around the USB ports, and enjoy working comfortably from a plush chair under sufficient lighting in a warm room of my house. As a consequence, the ignition switch no longer had the protection from the elements offered by the dash pad. With the keyed portion of the switch removed along with the dash pad, the operation of the ignition switch was performed with my house key, which has a wide blunt end about the length of the slot in the switch. This had been the situation for the past week. I don’t recall getting much rain during that period, just a whole lot of cold. The bike is parked in a carport at my house, free from any precipitation.
Just yesterday the bike started cutting out while running, and coincidently only when driving. After the unexpected loss of power, I looked down at the gauges and noticed that all lights had gone out. I naturally grabbed the switch mechanism resting on the handlebars. As soon as I grabbed it, the connection was restored and I was able to continue with little loss of speed. The second, and all subsequent times this happened yesterday (around five times in total, maybe four), it took just a little more than grabbing the switch. A few times I had to jostle the mechanism in my hand for a second before the power was restored. There was no need to pull over and stop during any of these situations.
Then, on my way home to address this issue in the comfort of my carport, I decided to make a quick stop at the grocery store. When I went to start the bike and go home, I once again placed my house key in the switch and turned it. I hit the starter button. The engine turned over for a fraction of a second and then stopped. I noticed that the headlight and all dash lights had gone out. I wasn’t too worried; I was sure that a simple jostle of the switch in my hand was all that was needed – but it never did work like it had been. The proper dash lights were never restored (the sign I was looking for as an indication that whatever connection was faulty had been restored). A few times the proper dash lights made an attempt to illuminate fully but did not. They would occasionally illuminate, however faint. Pressing the starter button during those times effectively does nothing.
[By proper dash lights, I mean the green neutral light and all the backlighting in the cluster, as well as the clock and the LCD gear indicator]
After further attention was given to recording exactly what symptoms the bike was expressing, I noticed that when I turn the switch all the way (passed the parking light/aux position) to the on position, the battery (charge) light makes a feeble attempt to illuminate, viz. appears as if less than the required voltage is being delivered.
This is when I removed the battery and walked home with it. I put the 8-month-old battery, with which I never had the first problem, on the trickle charger overnight. This morning the green light on the charger indicating a full or near full charge state was lit as expected. I carried the battery back to the bike.
Before re-installing the battery, I used sandpaper and contact cleaner to thoroughly clean all the connectors on both grounds to the frame (the one on the transmission next to the battery, and the one under the tank on the center frame rail). The symptoms were exactly the same, no change at all.
Further experimenting has led to some, I believe, strange symptoms. With the ignition switch in the on position and the kill switch straight up, the symptoms listed previously were witnessed. With the ignition switch in the on position and the kill switch to either side (in the “kill” position), the half-lit charge light goes out and a continuous buzzing emanates from one of the smaller relay switches under the tank. Judging from a diagram I have, I believe it’s the fuel injection relay. It’s on the forward side of the relay box and the furthest one to the left hand (clutch) side of the bike – one of the three similarly sized relay switches.
Honestly, as per a friend and long time Beemer guy’s advice, I haven’t really ever used the kill switch. He’s warned that they have a reputation for failure and advised I refrain from using it. So, I’m not real sure just how the bike is expected to respond to using the kill switch with the ignition switch on. But, these symptoms just strike me as probably not intended.
So, feeling that the problem is not the battery, I tried some further diagnostics.
********************
Again, when I turn the switch all the way (passed the parking light/aux position) to the on position, the battery (charge) light makes a feeble attempt to illuminate, viz. appears as if less than the required voltage is being delivered. All other instrument cluster lights (and both LCD units - clock and gear indicator), including the headlight, turn signals, brake light and horn do not operate when the switch is turned to the on position. And, of course the starter will not turn – no solenoid click – nothing.
With the ignition switch in the on position and the kill switch to either side (in the “kill” position), the half-lit charge light goes out and a continuous buzzing emanates from one of the smaller relay switches under the tank. Judging from a diagram I have, I believe it’s the fuel injection relay.
With the ignition key in the ‘off’ position – the red wire on the ignition switch has about 12.6 – 12.7 volts and the green wire has 0 volts.
With the ignition key in the ‘on’ position, and again not the parking light/aux position but the ‘on’ position – the red wire now has 2.34 volts! A very significant voltage drop. And the green wire registers a similar voltage.
This strikes me as unusual and completely WRONG!
I think I’ve conveyed all the symptoms that I have noticed or know to check for.
I’ve read some posts about measuring the voltage from the fuse panel but I’m not clear on what is expected and where. Additionally, I’m assuming that to properly measure at the fuse panel, I would place a probe on one side of the particular fuse slot (and only one particular side should register - because when you pull the fuse you break the circuit) and the other probe to ground on the frame. Is this correct?
Does anyone know of a good reference for what to expect at each fuse slot, and under what circumstances (key on or off)?
In my search of the Internet for anything that might shed some light on my problem and help with the diagnostics, I kept coming across Bertrand Vogel’s EFI/Electronic ignition K100 2v troubleshooting.
http://tomwade.me/motorcycles/technical/k100troubleshooting.pdf
While this is undoubtedly invaluable information every relevant K-bike owner should have, I believe I need help in the diagnostics that he mentions should be performed BEFORE consulting his troubleshooting guide. He starts his guide with this preface:
First, you have done all the basic troubleshooting such as: checking the fuses, ignition switch, kill switch, side stand switch (not applicable on early K100), transmission in neutral, clutch in, starter connection, Fuel pump connector on the fuel tank, and battery connections.
I believe I should start with these sorts of tests, in particular the ignition and kill switch troubleshooting. Does anyone know of a comparable guide that addresses these preliminary measures?
Thanks in advance for any assistance.