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Discussion Starter #1
I swapped another stator and r/r last night. The bike started up fine to morning but part way into my ride there was a slight jolt and the tachometer went to 0. I couldn't tell if the cylinder went as well since I was babying it until I got to work. I am confused since it felt fine for the first part of the ride. I am pretty sure I oriented the stator correctly. What could have gone wrong? The temp gauge and lights still work on the tach
 

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Possibly lost one of the coils, or there's a bad connection. The tach runs off one of the coils.
 

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Yes, a dead coil means one cylinder won't get spark.

Just check for spark on each cylinder.

I could be mistaken and the tach runs off one of the pickup coils instead. I remember seeing it posted, but forget at this point if it's an ignition coil or pickup coil. Either one would kill the spark on one cylinder.
 

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Discussion Starter #5
Thanks for your help. I'll check it when I get home. I'll know for sure by then if my cylinder isn't working anyway. Could something with the stator install have caused these issues if it's not a coil?
 

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Thanks for your help. I'll check it when I get home. I'll know for sure by then if my cylinder isn't working anyway
One cylinder running much cooler will show which one is dead.

Will need to crank the idle way up, by about 50%.

No, the stator shouldn't affect just one cylinder.
 

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Discussion Starter #7
It did idle when warmed up without adjusting the screw. It just seemed a bit off to me but that could be because I was panicking a bit about something for work combined with the tach not working
 

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So, according to the wiring schematic, ignition coil 1 (front?)'s primary coil's ground is tied to the tachometer.
That means that when working properly, the CDI box is providing a temporary path to ground each time a spark should trigger.

If the tach is dead, there's no path to ground, which means either a broken wire between the tach and the CDI box, the CDI box has failed, or the pickup coil that triggers the front cylinder has failed or has an open wire (black/yellow, black wire pair, lower pickup when looking under the engine cover).

I guess it's also possible that the primary coil in the ignition coil might have failed 'closed', somehow overpowering the pulsed signal, but that's unlikely.
 

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check for bad connections under the left neck cover.. all the wiring for the handle bars and gauges have connections there.

while changing the stator itself will not effect ignition, a broken wire on the pickup coils could, and they are delicate. and you may have broken a wire while working on stator
 

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Discussion Starter #10 (Edited)
It's definitely the front cylinder that's the problem but the coil tested 2.4 ohms on the primary and open on the secondary (the rear coil performed the same on secondary). The manual says 2 ohms Max but it's not THAT far off. Are the coils the same? They're part numbers differ by a letter but I can't imagine them being different really since the timing should be handled elsewhere in my mind

Also the ground wire to the coil tested well to ground and I'm getting power at the red hot wire at the ignition coil
 

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Discussion Starter #12
check for bad connections under the left neck cover.. all the wiring for the handle bars and gauges have connections there.

while changing the stator itself will not effect ignition, a broken wire on the pickup coils could, and they are delicate. and you may have broken a wire while working on stator
It happened about 10 minutes into the ride so I'm assuming that's not it based on that
 

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Also the ground wire to the coil tested well to ground and I'm getting power at the red hot wire at the ignition coil
Red hot is good, but I think it's a little more complicated than 'the ground wire on the coil testing well to ground'. That (from what I can tell) is the trigger for the spark when there's a brief, solid path to ground. The CDI box controls that via capacitors/mosfets/magic whatevers, so a straight ohm test doesn't mean everything is working correctly. It's the fluctuation of voltage between +12 and ground on that wire that makes the tach work and the coil fire.

Most likely culprit, as MTB says, is the pickup coil or the wires between it and the CDI box.

Second most likely is the CDI box.

Coil is probably fine.
 

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Discussion Starter #14
Also the ground wire to the coil tested well to ground and I'm getting power at the red hot wire at the ignition coil
Red hot is good, but I think it's a little more complicated than 'the ground wire on the coil testing well to ground'. That (from what I can tell) is the trigger for the spark when there's a brief, solid path to ground. The CDI box controls that via capacitors/mosfets/magic whatevers, so a straight ohm test doesn't mean everything is working correctly. It's the fluctuation of voltage between +12 and ground on that wire that makes the tach work and the coil fire.

Most likely culprit, as MTB says, is the pickup coil or the wires between it and the CDI box.

Second most likely is the CDI box.

Coil is probably fine.
How can I test those?
 

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How can I test those?
Pickup coils can be tested by checking the resistance between the two appropriate leads on the harness where it connects to the CDI box. 355 - 535 ohms. If you get an open line, you'll have to open the side cover and test between the terminals of the pickups themselves to see if the break is in the line or the coil is damaged.

If the pickups test OK, check the ignition coil primary 1.8-2.2 ohms, secondary 19-29Kohm. (did you already swap front and back successfully to rule out the coil?)

After that, the CDI box is sort of the only thing left, and there's not really a bench test for that component.
 

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Discussion Starter #16 (Edited)
I swapped in a new coil and it did nothing. I am currently doing resistance tests. Apparently Kawasaki has a CDI tester but it's around $120-150 so I'd recommend going to a dealer to use it if anyone else needs to go this route
 

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Discussion Starter #17 (Edited)
I think I found my problem. Grounded pickup coil. Everyone thanks so much for your help! I would have been dead in the water without you guys yet again. I love this community

Will the vn1500 pickup coil fit the vn750? If not I definitely ordered the wrong one
 
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