Hello from Oklahoma

Just joined the KZ Rider Forum family to, hopefully , gain some insight into the work I am doing on my Kawasaki motorcycle. I am rehabilitating my old bike for my son, and have had pretty good luck with everything until it came time to set the timing and adjust the carburetors. My bike is a hybrid. The fellow I bought it from was a mechanic at the Kawasaki shop who combined an engine, frame and body parts together from abandoned bikes in their shop. What I have is a 1975 Z1-B engine on a '76 frame with '79 LTD 1000 body parts..

When I bought it in 1980 it ran nicely, and I hope to get it back to that condition.. I have the official Kawasaki KZ900 Motorcycle Shop Manual and have used it with good luck until it came time to set the timing. It appears that the ignition circuit is grounded. When I had the ohmmeter set up across the points it always showed continuity no matter whether the points were open or closed. I am a new member and will search the data base before I send my second post (understand new members have to have 2 posts screened before they are put out for all to see).

Thanks

Welcome to KZRider
Lots of great help here
Your 1rst post is now visible as I have approved it .
We now review all new members 1rst and 2nd post to insure we limit / eliminate spammers from breaching our domain .
Posts are reviewed everyday, So you shouldnt have to wait long for approval.
We dont ok duplicate posts as counting toward open posting by new members
Dave

So let me give a brief history of my problem - the last time I rode the bike in 2008, the engine burned oil and 1 and 4 cylinders were not getting a spark so the bike sat in a garage until last January. Since then, the engine has been rebuilt. It appears the oil burning problem was too much clearance between valve guide and valve at the No. 2 intake valve. The spark problem is unsolved. After the engine was rebuilt and the carbs and ignition settings completed the engine started and idled nicely, but the first ride lasted only 1-1/2 miles before the engine was running rough which turned out to be carbon fouled plugs. It turned out that I had the float level in the carbs too high. After resetting the float levels, I could get maybe 30 miles on the odometer before the engine was running rough again due to fouled plugs. After cleaning off the plugs for the next couple of 30 mile rides, I decided to do some research which included the KZRider Forum and learned that a weak spark could also cause fouled plugs. A check of the plugs taped to the top of the cylinder head confirmed the sparking was less than desirable. I also learned that during the engine break-in period I should have been using the hotter B7ES plugs as my shifting gears at 4000 rpm was basically lugging the engine. i replaced points and condensers - rode the bike with the same results - replaced the coils - rode the bike with the same results, and finally replaced the B8ES plugs with the B7ES plugs and rode the bike for approximately 15 miles where during that ride the engine ran rougher and rougher with the last 5 miles the engine misfiring more than it fired. At this point I am totally frustrated and decide to start at the beginning. For the carbs, I lowered the needles to their leanest settings and started from scratch setting the points and timing - and this brings me to my problem that I hope someone can help with.

When I was setting the timing (getting the points to open on the "F" mark) the ohmmeter needle always showed a closed circuit as I observed the points open and close. I disconnected the points and condensers from the wires to the coils, and points and condensers checked out ok . Working my way back up the ignition circuit, I found that the circuit was grounded until I unplugged the Brake Light Failure Indicator Switch. This switch has a 3 pin connector, and I found that the 3 wires coming out of the switch all showed continuity no matter which 2 wires were selected. So my analysis is that the black ground wire to the switch is grounding the ignition circuit thru the Brake Light Failure indicator Light. This light and the ignition circuit share the same power wire.

I have researched the wiring diagram for the Brake Light Failure Indicator Switch and do not understand what it's telling me. My understanding of electrical components and their characteristics is minimal when you get into diodes, etc. What I am hoping is that someone can tell me if my switch is bad and shouldn't be grounding out the green wire that connects to the indicator light or if the switch is good. If the switch is good, then I guess I need to keep pulling apart wires until I find the source of the ground.

My process for checking components is to see if I get continuity between any component connection point and the metal case of the engine. Before starting my search for the ground, I took the battery out of the bike, disconnected the black/yellow ground wire from the engine case and unplugged the brown plug at the electrical panel to isolate the alternator, regulator, and rectifier. My ohmmeter is set to the highest scale. I'm using the wiring diagram for the KZ900 - A4 in my book. Any help would be greatly appreciated!!

I doubt the BLI switch would be the problem. You can test by running without it. Your points being shorted suggests a short in the lead wires maybe along the lower part of the frame touching the pipes. Had it happen.
Steve

Thanks, I appreciate the reply. Maybe I should further explain my process for isolating the ground problem. The wires from the coils to the points were checked to see if they were grounded after being disconnected from the points and the coils. So the wires were not connected to the wiring system at either end and my ohmmeter showed no continuity between them and the engine case - so they were not the source of the ground, but the primary wires coming off the coils still showed grounded. I next checked the coils in the same way - no continuity. Next I unplugged the 4 pin connector to the switches on the right handlebar, and the isolated switches showed no connection to the engine case. So what I'm saying is that after I isolated each component from the electrical system, I checked the isolated component to see if it was the source of the ground to the engine case.

Since the 4 pin connector to the right handlebar switches is the supply of power to the ignition circuit, I checked the power wire at this connector and it showed to be grounded. I proceeded to unplug electrical components tied into this brown power wire. Unplugging the BLI switch eliminated the continuity when checking the power wire at the output end of the of the 4 pin connector and the engine case.

I next checked the BLI switch by testing for continuity between the 3 wires coming out of it. All 3 wires showed continuity between each other no matter which 2 wires were selected. So it appears that the black ground wire to the BLI switch was grounding the power wire to the ignition circuit thru the indicator light on the instrument panel. I found the schematic diagram for the BLI switch in another KZRider forum and found that it is an electronic device which is above my head to understand. I was hoping that someone could tell me if my BLI switch was bad or maybe how to bench test it.

I will take your suggestion to leave the switch out and see if that makes a difference, but I would like to replace the switch if it is bad. Thanks for your reply.
Brad

Hi Brad, It sounds like you are over complicating your ignition problem. Points systems are pretty simple. There are two wires from two sets of points going to two coils. The handlebar kill switch should have nothing to do with the points leads,, if I am interpreting your posts correctly. Only the B+ power feed to the two coils goes through the handlebar switch. (Some bikes have a B+ ballast resistor inline) Dig up some info on the switch if you think it's bad, and make sure, unless you just like to blindly replace electrical parts.
As Steve said (been there, done that) , look for a burnt, smashed or shorted wire from the points to the coils. Unhook both ends, then check for continuity between the two.

Years since i had the old style points but i remember they had tiny insulating washers where the wire attaches and would short if washers omitted or broken or assembled incorrectly.
Another been there done that

Appreciate the replies from JR and old_kaw. I think I'm guilty of TMI - too much information, ha.

What I'm trying to find is some info on the switch (Brake Line Failure Indicator switch), but it has to be in layman's terms because the schematic that I found showed that the switch is an electronic device, and it's beyond me to understand if the switch is "normally closed" or "normally open" between the black ground wire and the green wire to the indicator light at the instrument panel.

I will keep digging. Thanks.

I would like to follow up and share what I have discovered while researching my original issue of setting the ignition timing using an ohmmeter. The shop manual says to connect an ohmmeter across the points and when the meter needle moves then the points have opened, and of course, that is when the plug fires. My issue was that after rotating the engine to where the set of points to be timed were closed and setting up the ohmmeter across the points that any further rotation of the engine did not cause the meter needle to move as I observed the points opening and closing. After an extensive review of the wiring diagram I found which circuits were the source of the ground. The solution to isolate the grounded circuits from the points I was trying to set was to turn the kill switch to "Off" and to block open the other set of points. After doing those two things, the ohmmeter worked per the book. I guess what really bugs me is that I have the official Kawasaki Shop Manual, and it did not address this issue. My bike has 200 miles on a rebuilt engine, and a friend helped me set the timing after the rebuild - I should have paid better attention!

All of this electrical work did cause me to clean all of the electrical connections and make sure they were tight. And I did find that the bullet connector between the kill switch and the coils did not have the coil wires fully inserted. I now have a bright, crisp spark : )

Appreciate all of the comments! I have been following the advice of KZRider members getting ready to , hopefully, solve my big problem - sooty, carbon-fouled spark plugs. As was stressed in the forum, you don't want to start any carburetor work until you are sure your valves are set and the electrical is in good shape, I am confident valves and electrical are good.

I have spent many hours reading the comments under "Carburetion" in the Technical Forums, and I believe I am getting a good feel for how the Mikuni carburetors work. I still have a few questions and therefore plan to start a new thread in the Carburetion forum. Thanks again.

Just a test