I have a basically stock '79 DOHC 750 except a Dynojet kit. whats going on is my bike a really modified visually and I've eliminated nearly all stock parts... ie, lights, gauges, ect... I have all new OEM harnesses throughout, new controls on the bars, a Reg/Rec from Oregon cycles, a Ricks rotor/stator, and a Dyna coil. There is obviously a ground/drain somewhere that I just CAN'T seem to figure out. She'll show proper charging at 14V's, but then one day out of no where it'll just suck a battery dead trying to get it home. What I need is advice and How-To on how to track this gremlin down. see, I can build a motor like nobodies business, but I still suck at 'lectrics... help please~
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killing batteries
- Thread starter Pongo
- Start date
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- Tags
- custom dohc electrical how to
I have a basically stock '79 DOHC 750 except a Dynojet kit. whats going on is my bike a really modified visually and I've eliminated nearly all stock parts... ie, lights, gauges, ect... I have all new OEM harnesses throughout, new controls on the bars, a Reg/Rec from Oregon cycles, a Ricks rotor/stator, and a Dyna coil. There is obviously a ground/drain somewhere that I just CAN'T seem to figure out. She'll show proper charging at 14V's, but then one day out of no where it'll just suck a battery dead trying to get it home. What I need is advice and How-To on how to track this gremlin down. see, I can build a motor like nobodies business, but I still suck at 'lectrics... help please~
amc49
CB750 Guru
The rotor on the DOHC is famous for testing as good all day long then not being so. They short internally and can charge at lower rpm but put bike out on the highway at steady higher rpm and then it does not, centrifugal force makes the wires then short to not charge as much. Slow back down and suddenly you have full charging again and it can show up on even new rotors. It does not happen on the SOHC because that field setup does not spin at max rpm like the DOHC does, it is fixed in place. Even a light drop of the DOHC on the right side can make it do that too, the rotors are really easy to break, I've had 3 on mine. The last one did just what I said, bike stayed charged up in city and then the problem only showed at steady state over 5500 rpm, the battery would then run down. Battery stayed up forever simply sitting.
So, if any of that sounds familiar you have an angle to pursue.
So, if any of that sounds familiar you have an angle to pursue.
