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Discussion Starter #1
My son’s fighting with the Highway gods. First his speedometer cable snapped. We fixed that. Then the ignition switch went bad. The key would only turn 1 notch. We replaced that and thought everything was fine. He made at least 2 trips to work and back (about 15 miles) with no problems. Then last Friday, on his way home the bike backfired a few times and died on the interstate. He was able to coast to the off ramp and into a safe parking lot. We loaded it in the pickup and brought it home.

Checking the electrical the battery was low so we put a Battery Tender on it overnight. The next day it started and when I checked the voltage it was charging about 14 volts at about 3000 rpm. Because we have no idea how old it is we started there. Since he had planned on replacing it last year before winter came we purchased a AGM from Batterys Plus. We brought it home and put it on a Battery Tender to fully charge. We also put one on his old battery and even though it had been fully charged over night it started to take a charge. The Tender on the new battery only stayed on about ½ an hour and then went into standby. The old battery stayed on for over 4 hours just setting on the bench which made us think it was only taking a surface charge and was shot.

We cleaned all the grounds and used dielectric grease on every connection when hooking up the new AGM and the bike started up better than it ever had. Almost instantly, and idled better as well without requiring any choke like it used to. He was still leery of riding to work without checking it out more so while he was at work yesterday I started the bike and double checked the voltage. It was low at an idle (over 12 volts) and climbed up for to over 14 when I increased the rpms then dropped back down. I left it run until the fan came on and then shut it off. Maybe 5-10 minutes. Several times I repeatedly started the bike, let it run and then shut it down, feeling sure it was good.

This morning he was going to take it to work and it started great, just as it had yesterday. He rode 2 blocks and it died on him. He said it started to stumble and try to run about 100 yards before dying completely. We first tried to jump it and it did start and run for maybe 30 seconds then dyed. We tried to jump it again and nothing. It wouldn’t even turn over. The starter does not do any thing. We loaded it up and brought it back home. I checked the battery and it shows about 14 volts.

The lights, turn signals and dash lights work as does the horn. No blown fuses. We have a backup JB so I tried that, nothing. There is no indication from examining the wiring that anything is bad. I can get the engine to turn over by jumping the solenoid but it won’t run even with the switch in the on position. Maybe the kill switch? But why would it short out while on the road?
 

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If you pull the clutch lever in, does it turn over?
yes=check neu sw
no=check connector on clutch lever sw
If you apply 12v to the starter sol. coil, does it pull in the starter relay and turn the bike over?
no=check ground on sol, if OK then bad sol.
yes=turn ign to on pos, set start/stop sw to run, and check for 12v on JB pin 11 when start button is pushed.
no=check Y/R wire behind left side cover for 12v with ign sw on
no=check ign sw connections (white wire=12v constant, Yellow wire=12v on pos)
yes=check B/R wire behind left cover for 12v when start button pushed
no=bad stat/stop sw or bad start button
yes=with 12v on pin 11, is there 12v on pin 13?
no=bad relay in JB or no ground on pin12....try grounding pin12 directly

try those and see what happens.......
 

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Discussion Starter #4
Battery

I kind of rounded up on reading my old analog Radio Shack multi-meter. It is right around 13 volts. By spending the last few hours pouring over the multitude of posts in this forum I decided to try some of the tests others had done, as well as reading what their problems were. I went out turned on the switch and held the start button down while moving the handlebars back and forth. Then I found a "sweet spot" where it turned over. I tugged on the harness coming out of the headlight and it started up. :smiley_th I found the problem area. Now I'll just start checking everything in that area. We replaced the puck when we changed the ignition switch so that will be first. I already have an extra that I bought on EBay just in case. I also ordered a R/R to have on hand as well. It could arrive today. Although I believe everything is fine with that for now.

I like his Vulcan so much I am looking for one to ride myself, so I am stocking up on the problem parts so that down time will be minimal. Once I get one like his I'll have two 750's. My other one is a H2 Mach IV that I bought new in 1974. I need to get the rear wheel re-spoked so I can take it out now and then but it is not a cruiser like the Vulcan.
 

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Should have bought my Vulcan.......... :doh:
 
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