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Maxi-fuse keeps blowing / Any ideas?

The 40A maxi-fuse in my 06 Lowrider keeps blowing. I was riding along w/ no issues when suddenly the bike went dead. No lights, nothing. Discovered the maxi-fuse had blown. Replaced w/ a new one and turned the ignition on. The lights flickered and then the fuse blew again. I thought water my have gotten somewhere and was causing a short because I had washed the bike the night before. I parked the bike in the hot sun for the afternoon to ensure it would dry out. A replaced the fuse and turn the ignition on. All the lights came on and stayed on. I thought everything was OK until I pressed the start button and the fuse blew again. I decided to switch the fuse w/ a 40A circuit breaker until I fix the problem. I checked all the wires that are easily assessible and can't find any obvious problem. Whenever I press the start button the circuit breaker trips; however, just turning the ignition on no longer causes a problem. Someone suggested by-passing the voltage regulator to see if that could be the problem. How would you do that?
Any other ideas? Thanks.
 
Sounds like an issue with the starter or starter solenoid. Unhook the battery and try removing the big hot wire off the starter solenoid. Make sure its isolated and not grounded. Hook battery back up. Turn it on and push start to see if it kicks the fuse/breaker then. Get back with us with the results.
 
I am amazed you have not blown any of the small 15 amp fuses. Has any wiring in the fuse box or ignition switch area been modified? Have any of the 15 amp fuses been hot wired or jumped out.
Has anyone added additional wiring for some kind of optional accessory without fusing it properly.

The Dyna needs a special jack to lift it. Check underneath near the oil tank for a crushed wire from using an improper jack.
 
I disconnected the voltage regulator from the bike and tried to start it with it removed. Same problem, as soon as I press the start button the circuit breaker trips. This is a self resetting circuit breaker. When the ignition is turned on, the lights come on as usual. When I press the start button they go off as the breaker trips and then come back on when I release the start button when the breaker resets. I took the starter relay out and then pressed the start button. This time the lights stayed on and breaker did not trip. I figured this might mean the relay was bad or the short was somewhere downstream of this relay. I went to the local Harley dealer and bought a new starter relay (cheap money) and also asked for advice. Not much help but said I was probably on the right track. I installed the new relay and gave it a try. This time the circuit breaker seemed to act differently. The lights dimmed significantly but did not go completely off when I pressed the start button. When I released the start button the lights remained dim and I noticed the breaker and hot lead wire to it were smoking. I pulled the breaker and wires immediately from the bike. The hot lead wire had melted badly and the breaker was very hot. I check the breaker for continuity and it was OK. I was worried I fried the electrical system of the bike. I put in a new maxifuse and turned on the ignition. The lights come on as usual and everything appeared normal. I decided to go back to the circuit breaker before I pressed the start button. With a new wire and the breaker installed I pressed the start button and the same thing happened. The lights dimmed and stayed dim. I quickly removed the breaker before the wire could melt. It was getting hot fast. I decided to go back to the original starter relay and see what would happen. With the original relay the lights go out completely when the start button is pressed and come on completely when it is released and the breaker resets itself. The wire to the breaker does not get hot at all when testing with the original relay. Very strange????
 
With the bike in Neutral, jump across the starter solenoid, does the bike turn over?
 
Replace the starter.......

I would agree based on what the bike is doing right now. But it doesn't explain what origially happen in 1st post..

OP says "I was riding along w/ no issues when suddenly the bike went dead. No lights, nothing. Discovered the maxi-fuse had blown".

It appears the 40 amp Maxi blew while riding without even energizing the start relay. But now you need to energize the relay. At least that is how I read it. Maybe true sequence of events was different. (?)
 
I have heard of cases where the starter hangs up while riding and the bearings finally freeze up. I would like to try Jack's suggestion and jump across the solenoid to see if the starter will turn the bike over.
 
Thanks for all the suggestions up to this point. I think it's the starter motor. I'm still confused how this circuit was activated during the initial problem. I had been cruising along at between 40 - 55 mph for ~50 minutes when the bike just went dead. However, everything since then is pointing to the starter. I have isolated this circuit working back from the starter button and it seems OK until you get right to the starter motor. I disconnected the solenoid connector (green wire) that connects to the starter motor. When this wire is disconnected the solenoid clicks (engages) as it should when the start button is pressed and the breaker does not trip. Therefore, it seems the starter itself is seized and causing a huge current draw that is blowing the maxi-fuse. It may be as someone suggested that the starter somehow engaged as I was riding along and then the bearings finally seized up. I have to go buy a 1/4" allen socket to remove the starter and then find a HD dealer that's opened on Sunday and buy a new starter motor. I'll let you know how I make out when finally fixed. Thanks again for all the help.
 
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