No Spark, Kill Switch issue?

Jeff N

Jeff N

New Member
I know you guys hear this alot! I have a 1973 K2 and upgraded with OHTOKC CDI ignition as well as a new battery and coil. I cannot get spark. Also, I replaced the wiring harness since the old one was chewed up by a mouse. The bike has a kill switch which could be giving me trouble. How can I by-pass the kill switch? Do I just connect the 2 wires running to it together?
 
kirrbby

kirrbby

Well-Known Member
To disable the kill switch, just disconnect the switch. That's it. The kill switch kills the engine by grounding out the ignition (black) wire. If you disconnect the black wire, the switch can't connect it to ground.
 
red69

red69

Well-Known Member
If you connect the two wires, you will have a permanent kill that will not allow the engine to run.
 
OLD CT

OLD CT

Well-Known Member
As kirrbby pointed out the black wire is the coil ignition wire. Make sure to follow that black wire from the new coil to the black wire on the conversion kit, make sure it's connected/hooked up.. Also, the green wire from the CDI kit should be grounded. I like to ground it on one of the coil mount bolts underneath. Make sure the new coil is mounted/grounded to a paint less area, exactly like the original was. The new coil should ''look and mount up'' exactly like the old coil. If not, you may have bought the wrong coil.
 
Jeff N

Jeff N

New Member
UPDATE:
I have spark when I run a jumper wire from the black wire coming from CDI ignition stator to ground (new CDI ignition is firing).
I have a weak spark when I run a jumper wire from black wire of stator to black wire of coil. I re-checked my ground which is at a coil bolt.
I do not have spark when I connect all wires as they should be to run the bike.
I have the following new electrical components:
CDI ignition
CHP wiring harness
Honda ignition switch
battery
coil
I would appreciate any or suggestions on fixing this. What would you do next?
 
Jeff N

Jeff N

New Member
upload_2021-5-12_10-23-51.jpeg
upload_2021-5-12_10-24-23.jpeg

This coil had 25 positive reviews and said to fit CT70.
 
OLD CT

OLD CT

Well-Known Member
The coil seems to be good for the bike and not incorrect. You do have the new ignition switch in the frame with the retainer ring tight, meaning it is properly grounded? Correct? Have you checked the taillight ground ''green wire'' is present also?
 
Jeff N

Jeff N

New Member
Oh man! I remember my new switch ring was not tightened down. The bike does not have a tail light. Should I just leave the wires from the harness unplugged? I won’t be back to bike until the morning and will let you know.
 
OLD CT

OLD CT

Well-Known Member
That's two ''ground points'' for the harness, and will give a weak spark if you are running thru the harness, like you should. lol.
 
Jeff N

Jeff N

New Member
I tightened the ignition switch and still get a yellowish weak spark. I do not have a rear light so the 2 wires from the harness are open and loose. What would you check next?
 
OLD CT

OLD CT

Well-Known Member
Make sure the coil is in tight also. Verify the ignition/harness is correct for a K2. If the spark is strong bypassing the harness, I would question the harness/ignition switch next. K1-K2 would be the correct parts. You own both bikes, so maybe swap to test...
 
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Gary

Gary

Well-Known Member
OLD CT said:
Make sure the coil is in tight also.
Click to expand...

Make sure it is grounded good to the frame as well and that the engine is grounded too. Technically all the ignition switch is doing at this point is providing a way to shut off the engine by grounding the ignition. The bike will run if you unplug the switch, just won't shut off
 
Jeff N

Jeff N

New Member
OLD CT said:
The coil seems to be good for the bike and not incorrect. You do have the new ignition switch in the frame with the retainer ring tight, meaning it is properly grounded? Correct? Have you checked the taillight ground ''green wire'' is present also?
Click to expand...
Hey Old CT you said "Have you checked the taillight ground ''green wire'' is present also?" Is this a green wire coming from the harness?
 
S

SeaBeagle

New Member
D2C5D85E-D490-42FE-9A78-FEC12A6CE908.png
I just put the CDI kit on my CT70. The original that he sent would not fire the stock coil. We troubleshooted on FB messenger for a week. He sent me an updated coil and CDI box. Worked like a charm.

Definitely make sure the coil is grounded well and the ignition switch is grounded well. The HT coil can be tested with an ohmmeter. Black wire to ground 2.1~2.3 ohms and HT lead to ground 9~11Kohms (no plug cap). Or use an old coil test rig.
 
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Jeff N

Jeff N

New Member
SeaBeagle said:
View attachment 71372 I just put the CDI kit on my CT70. The original that he sent would not fire the stock coil. We troubleshooted on FB messenger for a week. He sent me an updated coil and CDI box. Worked like a charm.

Definitely make sure the coil is grounded well and the ignition switch is grounded well. The HT coil can be tested with an ohmmeter. Black wire to ground 2.1~2.3 ohms and HT lead to ground 9~11Kohms (no plug cap). Or use an old coil test rig.
Click to expand...
Who is the "He" that you bought the CDI kit from? Is it OHTOKC? What kind of updated coil and CDI box did he send you?
 
Jeff N

Jeff N

New Member
I cannot see a spark at the spark plug when holding the sparkplug against the engine while kicking the motor over. When I place my test light pointer into the sparkplug cap and ground it to the motor I have a bright test light. Does this mean I have a good spark?
 
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