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Discussion Starter · #1 ·
Ive been haveing trouble with the F3 dying after if warms up, the guages start jumping around and then everything dies.

So I put multimeter to the battery and found that the bike starts on the new, charged battery just fine, and the voltage across the terminals is 13.4 volts as the bike warms up (12.8 volts with the bike off).

After a few minutes tho, the voltage drops to 12.8 and then slowly drops to 12.7..... .6......... 12.5........... .4 .3 and so on.
Till the bike dies.

So im guessing that the charging system dies out as the bike warms up. What could this be? How should I go about testing? I have the fault finding chart that was posted a while back, and ill be trying that tomorrow,, but would be nice to know if you all know what to look for.

Thanks.
 

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Could be the voltage regulator. They are notorious on some of the Honda's. They can go out either way it seems. MEaning, they can allow too much voltage(17v on my superhawk) to get to the battery.......or too little.

Could also be a wiring issue........electrical is hard to diagnose as it is, let alone over the net.

Good luck and let us know what you find.
 

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I was going to put my money ($0.02) is on the battery until I re-read your post. You say you have a new, charged battery, and it's voltage drops from what it should be in a few minutes? Hmmmm... I think Shane has good words. I'm not sure how easy it is to diagnose a voltage regulator, but I'd probably start there. And pull your battery out of there and keep it charged up. Sounds to me like your bike will kill your battery in short order.
 

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there is a good chance the rectifier could be getting hot and causeing a direct short to ground, I`m not sure but up in the rear of the bike probibly bolted to the subframe you will find an aluminum finned box, the best I can tell you to do run the bike again and when it begins to drop power shut off the bike, unplug the rectifier and test each connector with an ohm meter for a short to ground, let us know how it works out for you
 

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GSXshawnF said:
there is a good chance the rectifier could be getting hot and causeing a direct short to ground, I`m not sure but up in the rear of the bike probibly bolted to the subframe you will find an aluminum finned box, the best I can tell you to do run the bike again and when it begins to drop power shut off the bike, unplug the rectifier and test each connector with an ohm meter for a short to ground, let us know how it works out for you

The regulator/rectifier IS bolted on the subframe of the F3's/superhawks/etc, but it is NOT finned. It has an open metal backing that touches the subframe, and relies on this for cooling. This seems to be part of the problem with the design.........
 

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Discussion Starter · #6 ·
thanks guys,,


i checked the regulator/rectifier today.

First thing i noticed was that when i disconnected the wires from it, the wire connector on the wire side, not the rectifier side, had some black melted stuff on two of the yellow wires. Did the wiring harness resistance test on the wires and they came out ok, except for the gunk causing the intermittent open with the test leads.

The regulator rectifier had opens across all of the pins when i tested, so i think i may have to replace that. Hopefully its that and not the stator,,,
 

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ElectrixUSA (sp) has a reg/rec test procedure on their sight.

NOTE: HEAT does not kill Rec/recs. I spoke with one of the head engineers at ElectrixUSA whe I was having r/r issues with my VFR and they had just got done running some test using an r/r cooled with ice water (epoxy sealed and put into a bucket). No changes in behavior.

If you have to buy an new r/r, I reccommend ElectrixUSA. They have (or had) a one-year warrenty on parts last time I checked.

Also (can you tell I've done this before?) go ahead and replace the grounding cable from your battery to where ever it goes. Breed and Co. by UT off of Guadalupe sells 4ga welding cable and appropriate connectors to use to repace this. It might be over kill, but you'll never worry about grounding ever again :)
 
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