This makes me wonder if the previous guy tried any other changes and forgot to change back? I hate to be a pessimist, but I would check/trace the best I could to make sure the wiring matches the diagram, and check the key switch as noted in post #17.
71- z 50 Head light goes out when I hit the brakes .
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This makes me wonder if the previous guy tried any other changes and forgot to change back? I hate to be a pessimist, but I would check/trace the best I could to make sure the wiring matches the diagram, and check the key switch as noted in post #17.
ctbale
Member
funny the WD shows the front brake switch NC. Probably nothing.
Super duper confused.
Did the problem start with the 40 year mechanic engine rebuild?
"I've had this problem for a long time and the back story is - had the engine rebuilt 5 years ago"
You said the 40 year mech put in coils and wiring from a 68-69 and you switched it back?
Just trying to figure out which WD to look at. I think the correct WD is in Post 14, a K2 with no battery???
Sounds like you got the white correctly connected from the key switch to all three brake switches with no shorts or "detours'
By looking at THAT WD it looks like the Gray (C1) and the Blue(C2) are swapped. Maybe even the red (C3)
When the key is in the Headlite position, the red wire (C1) feeds the headlite/taillite AND the Gray wire feeds the White wire that goes to the brake switches. (C1 to SL) When the key is in pos 1 no headlite or tail light the brake lites are powered by the blue wire (C2)
So if this is a problem starting with the 40 year expert, (that likes to reroute white wires) and the switch has always been fine and is original, my money is the coil is wrong? or misswired. Because when you hit the brakes with the headlite on, the gray wire should be powering the brake lites and the red should have enuf power to keep the headlite/taillite "on"
Super duper confused.
Did the problem start with the 40 year mechanic engine rebuild?
"I've had this problem for a long time and the back story is - had the engine rebuilt 5 years ago"
You said the 40 year mech put in coils and wiring from a 68-69 and you switched it back?
Just trying to figure out which WD to look at. I think the correct WD is in Post 14, a K2 with no battery???
Sounds like you got the white correctly connected from the key switch to all three brake switches with no shorts or "detours'
By looking at THAT WD it looks like the Gray (C1) and the Blue(C2) are swapped. Maybe even the red (C3)
When the key is in the Headlite position, the red wire (C1) feeds the headlite/taillite AND the Gray wire feeds the White wire that goes to the brake switches. (C1 to SL) When the key is in pos 1 no headlite or tail light the brake lites are powered by the blue wire (C2)
So if this is a problem starting with the 40 year expert, (that likes to reroute white wires) and the switch has always been fine and is original, my money is the coil is wrong? or misswired. Because when you hit the brakes with the headlite on, the gray wire should be powering the brake lites and the red should have enuf power to keep the headlite/taillite "on"
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ctbale
Member
Stator Repair kit, Z50 K2-1978. Stator Assembly Kit, reproduction- This kit is as close to the original Honda as you can get.. Now with your original backing plate you can totally rebuild your stator for less than $50.00. This kit comes with all of the needed components for a complete rebuild and tune up to your stator assy. As pictured, kit includes the following, both coils, condenser, points, wiring, screws, O-ring, oil seal. Unlike other aftermarket stator kits out there, these were made specially for the K0 so there is no guessing about what color wire goes where nor are modifications necessary.
This is from CHP website for kit 165 Wire colors are different then oem, and there is a contradiction in the description K2? K0??
You do have a K2 original wiring harness right?
This is from CHP website for kit 165 Wire colors are different then oem, and there is a contradiction in the description K2? K0??
You do have a K2 original wiring harness right?
TENACIOUS T
Member
I went back and edited post 16 -the correct wiring diag. are #11 and #14 . Looks like the harness is new and the wires seam to match . The Key switch is original . It just works so good ( day = brake light nice and bright ) ( night = HL & TL good ) but put on the brake = HL goes out , TL/ stop light go dim ???
TENACIOUS T
Member
I don't know the answer to that other than he could not figure it out ether . So that is big reason why I decided to replace with new parts hoping to fix it .
ctbale
Member
TS Time!
EDIT: Pull the tail light bulb, see if the HL still dies with brakes applied, bulb might be pulling too many amps/watts? EZ test any way
Get a 6volt source, connect neg to a good ground
Disconnect the white square molex connector at the engine/stater. (I am guessing thats the connector description, never actually worked on a honda 50! lol)
Apply following 6VDC to wiring harness, not eng/stator (I am guessing you dont have a 6VAC Source)
1. With the Key in Pos 2 put 6v on the red wire. You should get HL both High and low, High beam Indication and tail light. Your brake lights should not work. (I think you did this test.
2. Leave Key in Pos 2, 6v on gray wire, you should get brake lites from all three switches, then switch to Pos 1, no brake lite from any switch. and No HL/TL in either test
3. Now leave key switch in Pos 1 and put 6v on Blue wire, all 3 brake light switches should illum brake light, then go back to Pos 2 and none should Illum brake lite. No HL/TL in either test
WD says no lights should work when key is in off position and 6v on red, gray or blue. Might want to test that also
PS, you will get a "BUZZ" on most DVMs on the brown wire if that brown wire leads to a lamp. Its seeing ground thru the filiment.
Also curious that your Ohm values are so different then Allen's
EDIT: Pull the tail light bulb, see if the HL still dies with brakes applied, bulb might be pulling too many amps/watts? EZ test any way
Get a 6volt source, connect neg to a good ground
Disconnect the white square molex connector at the engine/stater. (I am guessing thats the connector description, never actually worked on a honda 50! lol)
Apply following 6VDC to wiring harness, not eng/stator (I am guessing you dont have a 6VAC Source)
1. With the Key in Pos 2 put 6v on the red wire. You should get HL both High and low, High beam Indication and tail light. Your brake lights should not work. (I think you did this test.
2. Leave Key in Pos 2, 6v on gray wire, you should get brake lites from all three switches, then switch to Pos 1, no brake lite from any switch. and No HL/TL in either test
3. Now leave key switch in Pos 1 and put 6v on Blue wire, all 3 brake light switches should illum brake light, then go back to Pos 2 and none should Illum brake lite. No HL/TL in either test
WD says no lights should work when key is in off position and 6v on red, gray or blue. Might want to test that also
PS, you will get a "BUZZ" on most DVMs on the brown wire if that brown wire leads to a lamp. Its seeing ground thru the filiment.
Also curious that your Ohm values are so different then Allen's
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If you've tried all there steps above, including connecting a battery and checking all lamps including the brake light, I believe you've narrowed it down to the stator. If you want to be 100% certain and remove all doubt, connect 3 jumpers from the positive post on the battery to red, blue and green wire on the plug for your wiring harness. Then cycle your key switch.
I have a spare stator that I can send you for test, sell outright, or whatever works for you. Just shoot me a PM and let me if you're interested. I think it already has new points and condenser so you should be able to test without doing a lot of work. Electrical problems can be a PITA, so I'm willing to do what I can to help you out.
I have a spare stator that I can send you for test, sell outright, or whatever works for you. Just shoot me a PM and let me if you're interested. I think it already has new points and condenser so you should be able to test without doing a lot of work. Electrical problems can be a PITA, so I'm willing to do what I can to help you out.
TENACIOUS T
Member
I want to give a big thank you to every one that helped and your offer allenp42 on this problem . Winter is here and I'll put it's blanket on . Maybe an answer will pop up before spring . If I ever ride it at night - I will just not hit the brakes !
IMO, Allen gave you the right advice. Either work very quickly, or place an inline fuse in your test circuit. A fuse would be more convenient, in a real-world way, allowing you to cycle the lights as happens while riding. If it blows, you know there's a short somewhere. Now is probably the most convenient time of year to pull the harness from the bike. If it's the original, there's a fair chance that you'll find an insulation break somewhere, once it's been unwrapped. OTOH, I get the sense that your frustration level has reached the point of burnout and you just need a break. Believe me, we've all been there...
I hear you; I sometimes do the same. When this project moves back into your radar screen, just let me know.
I know you've put your puppy to sleep for the winter, but I just happen to stumble across something that I wanted to put in writing as memory plug when you resume work on your project.
Based on your wire colors, it appears that you have a TBParts coil? They (TBParts) noted that grey was not available so they used green.
Also, I double checked (more like triple checked) the values from 2 1974 Z50's and 2 1977 Z50's that have an original untouched stator. I had always assumed the stators were the same....but they are not. I feel sure that if I put a 77 on a 74 and vice versa and the lights would still work - They only use one winding. I don't have the same feeling about a K2 because of how the key switch works on a K2.
Based on the wiring diagrams I have, the stator wiring on a K2 looks the same as a K5 (1974).
I also don't expect you'll get the same resistance values as I show unless we're both using the exact same DVM.
The values I get for a 74 are: Red = ~1.4, Blue = ~0.5, Gray = ~0.7. What's important is that red is the highest and blue is the lowest.
On both my 77's, the values are: Red = ~0.5, blue = ~0.4, Gray = ~1.1 Note that grey is the highest, and not much difference between red & blue.
Don't want to overwhelm you, but I just want to document it for the future...to help me remember.