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Discussion Starter #1
Hi guys! I'm trusting that your collective wisdom will be of some help. I've got two 1995 Vulcan 750's. The one had a slightly bent frame from an accident last year. The other had starting issues that I assumed were the result of a bad stator. The motor in the "bent frame bike" had fewer miles, no stator issues, and ran great, so my thought was to just remove the motor with the bad stator (I assumed) and put in the motor from the other bike. I did this with relatively few complications. But strangely the bike with the new motor is having exactly the same starting issues as it did with the previous motor. Right away you notice that the starter sounds weak, it turns over a few times times, and gets weaker and weaker until it won't turn over at all. Could I be looking at a regulator/rectifier issue? I'm at a loss. Thanks for any help and advice.

James
 

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1986 VN750
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Hi guys! I'm trusting that your collective wisdom will be of some help. I've got two 1995 Vulcan 750's. The one had a slightly bent frame from an accident last year. The other had starting issues that I assumed were the result of a bad stator. The motor in the "bent frame bike" had fewer miles, no stator issues, and ran great, so my thought was to just remove the motor with the bad stator (I assumed) and put in the motor from the other bike. I did this with relatively few complications. But strangely the bike with the new motor is having exactly the same starting issues as it did with the previous motor. Right away you notice that the starter sounds weak, it turns over a few times times, and gets weaker and weaker until it won't turn over at all. Could I be looking at a regulator/rectifier issue? I'm at a loss. Thanks for any help and advice.

James
Starting the bike relies on the battery, and the battery alone. A stator being bad should not affect starting, though running it with a bad stator could cause the R/R to fail. I had an R/R failure and it still allowed the bike to start. I am not sure if a different type of R/R failure could lead to a no-start situation.

1. Is the battery charged? It should read around 12.5v with the bike off.

2. Is the battery an old wet-cell or new-style AGM? AGM makes a world of difference.

3. What about the spark plugs? Both VN750s I purchased had copper plugs in them, once I changed them over to Iridium they both start first touch of the starter. The 1990 I bought literally would turn over 20-30 times before it would start; that was good on the starter I am sure.

To me, it sounds like the battery is drained if it can only turn over three times. Also, check your wiring - you could have a loose or corroded ground somewhere.
 

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Discussion Starter #4
Thanks so much for the quick reply. I'm planning on moving the r/r from the other bike, and I'll check all of the ground points, and the other items you mentioned. Once I'm done (it will probably take me a few days to get to it) I'll let you know how it turns out. Again, thank you!
 

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Thanks again for the input. Here's what I did. I went back and checked all the ground points and cleaned them up. I know the battery is good but just to be safe I took it out, trickle charged it during the day, made sure it was holding its charge the following morning (read 12.8), put it back in and tried again. It started ok and I thought everything was fine. But later in the day the battery was low once again. I started to think along the lines of a short somewhere in the wiring harness. So, I changed out the wiring harness. I'm pretty sure that solved the problem and everything looked fine (the battery sits there without losing its charge). But once I got the tank back on and tried starting it up I got nothing. Doesn't turn over, not even a click. The lights work, turn signals, horn, etc., the battery is strong, but nothing happens when I go to start it. So I may have solved the original problem and created another. I've checked and double checked all of the connections and can't find anything out of place. Any help or suggestions would be appreciated.
 

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check your lockout switches on the clutch and sidestand as well as the neutral switch.
 

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Discussion Starter #8
I paid attention to the kill switch (though I wouldn't put it past me to miss that). I'll check the others and see if that does anything. Thanks!
 

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Discussion Starter #10
Other than checking that the connection is good, is there something else I can do to confirm that the switches are functioning correctly?
 

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Don't know about the clutch switch but the side stand switch sticks in give it a spry with something like wd40 and clean it up a bit press it in and out and see if that works it loose.
 
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