QuestionOk, I will explain in detail the problem I am having so it may be easier to diagnose. 3 months ago I bought an 84 Honda Nighthawk cb650sc. Great bike, very fast, very quick to pick up speeds. Anyways, upon purchasing the bike I noticed it needed some small cosmetic repairs and a few other misc repairs. One was the ignition switch. It seems it had failed and the guy I bought it from said the previous owner before him had wired up a toggle switch to the solenoid to power the bike. I could flip the toggle on, all the instruments and lights would come on(except the rear signal lights) and I used the push button starter to give the bike life. I rode the bike for 3 months this way, and it ran fine except for a slight wobbling, which may be a bad tire or bad shocks. Both could use a replacement for sure, but for lack of money I kept the rides short. I have no money for a repair manual(yet).
The front blinkers did not flash but would power on. Rear lights never blinked, or even power on, but the brake light did. I figured it was a fuse.
I was driving the other night and noticed the rear tail light warning light was on, on the instrument panel, and decided to stop for gas and try to locate the fuse box. Its right under the headlight. I guess I never thought it would be there. Anyways, it has 4 fuses. The correct fuses are all 15 amp, but when I looked at the box there was a 25/15/15/15 in there. I pulled a 15 from the middle to see if it was blown(the bike was still running and I noticed a metal wire jumping the 2 middle fuses. Weird, i thought. I plugged the non blown fuse back in and immediately fried it. I was left with only a headlight and no other lights, not even instruments. I drove home since I did not have replacement fuses. After I got home, I replaced that fuse, then thought id pull that jumper wire someone put in there to see what happened. I plugged the fuse back in and blew it immediately. I was out of fuses so I let the bike sit for 3 days until I got my paycheck. It rained on that last day.
Now, I try to start the bike and I get nothing but the tailight to power on. I completely strip the wire harness(entire bike) to locate a possible problem, and I find 2 wires near the neck of the bike had been crushed, and were also soaking wet inside the wire harness sheath. I dried them, and reconnected, and tried to crank the bike. Its not registering no power, no guages, and no tailight now either. Complete power loss. I used a screwdriver to arc the solenoid and it will try to kick over, but there is no fire to the plugs, and no other electrical power at all to the bike. No horn, nothing. Earlier I mentioned the toggle being wired to the solenoid. Its supposed to have a 30 amp main fuse screwed in between the 2 screws(+/-) on the solenoid, according to the owners manual, but it did not have one when I bought the bike. I installed a new fuse, thinking id get lucky, and nothing happened.
Im completely baffled now, and have no clue what to do next, not that I had much clue to start with. I am thinking im looking to hard and the problem is a lot simpler than I think, but I am lost on what to do next. I do not have a great income at the moment, or Id simply hire a mechanic. Please help, if you can. I will take any directives/advice you can offer, and will thank you in advance!
P.S.(sorry for the really long explanation, just figured it may help)
AnswerJamie, without knowing which wires were damaged and the state of your charging system, battery charge level, etc. it is pretty hard to guide you specifically to the "cause" of the the problem.
Obviously you have an electrical draw that is beyond the fuse's ability to regulate.
You need a simple $5 12v test light available from any auto parts store to start with, then use the diagrams at http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php CB650SC as a guide for the circuitry. Start with a fully charged battery always. Check the ignition switch connector base for any damage to the connector itself and see if the base is loose on the switch, as well.
The front turn signals have a double filament bulb, one for running light and one for turn signal function. The rears are turn signals only. Front running lights will go out when you select high beam function. Headlight goes OFF when you hit the starter button, then resume. If that starter button collapses internally, then you will lose one or both functions.
Honda's wiring colors are consistent from front to rear so you need to check each wire color to where it is going and then determine if the component is good or not.
The 30 amp fuse on the solenoid is the fusible link for the whole electrical system, so that has to be fully functional as the first step. Disconnect all the external components from the harness and then start plugging them back in one at a time.
The inner field coil on the alternator is a known failure point in these engines.
Go to www.electrosport.com for troubleshooting guides and the known failures list.
When you turn the ignition switch to PARK position, only the tail light comes on, so always be sure NOT to pull the key out in the PARK position when you leave the bike.
I hope this helps...
Bill Silver
