I worked on this charging problem. My 650 did not charge, even with the headlamp off. I finally found the reason, that I exposed already here. A summary :
- The engineer who designed the alternator at Hitachi made an error. The two parts of the rotor are on each side of a thin metal sheet which holds the excitator winding. This forces the field lines in the stator (from a minus to a plus magnetic pole and so on) to cross the median plane of the stator, in a sort of zig-zag path. It increases badly the resistance of the magnetic circuit to the field, as each sheet of iron is separated of it's neighbour by a varnish coat, in order to suppress Foucault currents in the stator and magnetic losses. - To counterbalance this weakness in the stator, it was necessary to boost at the limit the magnetic field in the rotor, i.e. to increase at the limit the number of turns and the current in the excitator winding. As a result, this winding is nearly over the limit for heat dissipation. After a long enough time (say one hour or more) riding, with the headlamp on, if the weather is hot (summer) and the cooling bad (ride in traffic jams), temperature at the core of this excitator winding excesses the limit of the insulation material around copper wire. You get short circuits beetween neighbour wires. - In some cases, the alternator stops completely charging, and the circuit of the excitator winding (black/white wires) is found open. This could be the best case. In some other cases, this circuit is found "nearly correct", with a resistance of say 3 ohms instead of the nominal value of 6 Ohms. This is a very bad situation, as it can burn the transistor which regulates the current in this winding, inside the original regulator (Shindengen). And, on my bike I found that this transistor was burnt in short circuit position, thus allowing the excitator winding to be fed permanently with the 12 V voltage. The previous owner of the bike changed the stator. But, as the regulator was burnt, very soon this overvoltage and overcurrent in the stator again burnt the stator. He ended by selling the bike after some hundreds of bucks to the Honda dealer, who did not understand what was happening. - I changed the regulator to a modern one (Electrex), with current limit on the output (FET PWM). I bought a rewired alternator. I changed all the turn signals, rear light and headlamp bulbs to LEDs. On the headlamp, I have no longer a high/low beam but just one position H4 compatible LED, which is ideal to ride in daylight (clearly visible from others), but bad at night : lights hardly to ride at 60 km/h though being too bright for people in front of me. But I don't ride at night, so... I thought selling this 650. But it's so fun... now I found how to use it and I enjoy. Anyway it was too weak (max load 160 kg) to support my honey's and my weights alltogether with luggage for long drives. So I bought for 1100 euros a 1983 Yamaha 900 XJ for long rides at two with luggage. Of course I have some problems with the Yam (bad groundings...) but this is part of the fun. This two bikes scheme is, IMHO, a good deal and I will probably go on this way. My two cents. If this can help... At 19:10 26/05/2009 -0700, you wrote: >Chuck, where would you mount it to the engine. I'm came off when I >replaced the battery last time. Did run a second ground to the frame. > However I am having a charging issue, so if I need one to the engine >to improve that I will try it. > >Wayne >83 CB650SC --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
