81 kz650 low voltage to cdi box
- agrestixrock
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81 kz650 low voltage to cdi box
14 Mar 2018 07:24 - 14 Mar 2018 07:27
Okay I have other threads but there is no more replies. I have finally found the issue but cannot resolve it yet. For my CDI box to fire i have to get 10.5v to it but I'm only getting 9.5. My kill switch is very hard to turn so I tried holding the 2 wires together and trying it. Still only getting 9.5v. I'm guessing I'm missing a main ground as I tried to see what voltage i was getting to the main fuse to see if I was only getting 9.5v there when I put the positive lead to the fuse it blew. I do not have a main ground to my frame and cannot find where it's supposed to ground from like what component or connector. I have the lead just no idea where it goes. Please help I'm so close to getting Her running BUt NEed IDeas
Last edit: 14 Mar 2018 07:27 by agrestixrock. Reason: No pic
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- Patton
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Re: 81 kz650 low voltage to cdi box
14 Mar 2018 07:46
If the ignition grounding is being done through a chassis connection, would change it to an engine connection.
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- Nessism
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Re: 81 kz650 low voltage to cdi box
14 Mar 2018 08:00
The ground wire you show in the photo has an aftermarket bullet connector on it suggesting some meddling. You should have a ground from the engine to frame and/or to the starter.
BTW, your bike doesn't have a CDI. It's an ignitor.
BTW, your bike doesn't have a CDI. It's an ignitor.
Ed
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
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1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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- agrestixrock
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Re: 81 kz650 low voltage to cdi box
22 Mar 2018 09:32
determined the only thing drawing power is the starter motor. will make sure it is grounded correctly as it drops the voltage to about 8.7v when its on. no other lights or anything is connected just to see. how can i determine if its drawing too much power and is there any way to fix it? i noticed the previous owner bypassed the starter lockout switch when he hotwired it with a toggle switch.
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- Nessism
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Re: 81 kz650 low voltage to cdi box
22 Mar 2018 11:36
The starter motor gets its ground from the case, which gets its ground from the engine proper.
Ed
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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- agrestixrock
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Re: 81 kz650 low voltage to cdi box
22 Mar 2018 12:00
okay hmm. how would i check how much power it is drawing? and how would i fix it if its drawing too much? the starter lockout switch doesnt have a resistive circuit does it?
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- Scirocco
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Re: 81 kz650 low voltage to cdi box
22 Mar 2018 12:56
It looks like your starter motor need more current as normal = voltage drop by a bad electric connection under heavy load.
Try to remove the starter motor out of his engine housing and ground the starter motor to the engine case, which gets its ground from the battery negative. The starter motor should spin freely with out any voltage drop lower than 12 Volt.
The internal starter brushes or commutator could be weak, short cut or worn out.
Try to remove the starter motor out of his engine housing and ground the starter motor to the engine case, which gets its ground from the battery negative. The starter motor should spin freely with out any voltage drop lower than 12 Volt.
The internal starter brushes or commutator could be weak, short cut or worn out.
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- agrestixrock
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Re: 81 kz650 low voltage to cdi box
23 Mar 2018 07:13
i will give it a shot, just to make sure you are saying to pull it out, put it to engine block and press the start button then check the voltage drop while doing so?
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Re: 81 kz650 low voltage to cdi box
23 Mar 2018 07:36
Yes, do so to confirm you have no voltage drop on the igniter and got sparks on the plugs.
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- agrestixrock
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Re: 81 kz650 low voltage to cdi box
23 Mar 2018 07:51
okay thank you! i will try when i get home. if it is good, do you know anywhere i could find parts to fix the starte r motor?
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- JMKZHI
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Re: 81 kz650 low voltage to cdi box
23 Mar 2018 09:07 - 23 Mar 2018 09:08
Since the kill switch is hard to turn, the problem may lie therein. Possibly either from corrosion or some sort of damage.
I would open up the handlebar control switch for inspection & test for voltage.
I would also check for voltage at the ignition switch connector. W & Y. and the handlebar control connector.
The main engine grounding point is on the right side near the oil filler cap. It is the main/fat ground wire that goes directly from the battery neg (-) to the engine. I am not aware of a dedicated ground to the frame. I think the chassis grounding is thru that main engine ground & the black-yellow grounding circuit, also at the battery neg (-) terminal.
1981 KZ650-H1 wiring diagram.
To enlarge the wiring diagram. open the image in a new window, then click again to enlarge. It's big.
I would open up the handlebar control switch for inspection & test for voltage.
I would also check for voltage at the ignition switch connector. W & Y. and the handlebar control connector.
The main engine grounding point is on the right side near the oil filler cap. It is the main/fat ground wire that goes directly from the battery neg (-) to the engine. I am not aware of a dedicated ground to the frame. I think the chassis grounding is thru that main engine ground & the black-yellow grounding circuit, also at the battery neg (-) terminal.
1981 KZ650-H1 wiring diagram.
To enlarge the wiring diagram. open the image in a new window, then click again to enlarge. It's big.
Last edit: 23 Mar 2018 09:08 by JMKZHI.
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- Nessism
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Re: 81 kz650 low voltage to cdi box
23 Mar 2018 11:45
Have you tried bump starting the bike to see if you get spark that way?
Ed
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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