Dead Battery

[CHRISZZR600]

Hi 416, thanks for replying....i have 5 wires..red,yellow,green,pink and black....i have no idea which one is which..lol....i'm no electrician here.!! I'm guessing black is earth? is there any way to test it off the bike? I prodded about with the meter earlier with it on the bike and running, but none of what i saw made any sense to me..i tested on AC and DC, but i don't honestly know what i was looking at. If the lighting circuit is still ok,(headlamp works),and the alternator is fried on the charging side...could i splice into the headlamp wires to keep the battery going a bit longer...or am i mad??? Reg/rect is a Shindengen SH542-12 3.3 has anyone got one? i don't mind paying..but i need to get one soon, either that or the bike will have to go....Cheers for any help, Chris.

[416cc]

First off, I would advise you to get a manual for the bike as it explains far more than I want to type on here.

But the wiring from the regulator/rectifier is green is earth, red is +12vdc charging voltage, yellow is AC input from the alternator, black is regulated +12vdc the pink wire is the feedback to the alternator for voltage regulation.

If you put your multimeter, set to about 20vac onto the yellow wire coming from the alternator going to your rectifier/regulator, you should have about 15vac, with the other end of the multimeter to an earthing point on the chassis of the bike. If this voltage is good (supposing that it is a 12v battery) then this shows that the alternator is chucking out the required charging voltage in its barest form, before it is rectified & then regulated. Ignore the headlight, as it's most likely to be fed from a seperate lighting coil within the alternator, & not affected by the battery.

Have you checked the connection going from the -ve side of the battery to earth? If this is bad, as in a high resistance reading or anything a lot higher than zero ohms, then this is likely to be where your problem is, as the chassis/frame is used as the method by which all negative voltages are connected back to the battery. There should be several earth/chassis connections, the green wires, that should be good. There's normally one by the coil, one from the -ve sid of the battery, as well as several inside of the headlight. If the multimeter was connected to a known good earth/chassis point, then, using the other multimeter lead go to various other green wire connectors on the wiring loom. If any of the resistance readings are high, there may well be a broken wire somewhere within the loom.

The link that I posted before is to a supplier of electrical items for your bike. Electrexworld are very good for many dirtbike components, & are usually a lot cheaper than OEM parts.

[CHRISZZR600]

416, thats brilliant...thank you very much.....only just got home so it's too late for me to check it out tonight,but i'll do it at the weekend. No-one has ever explained anything in so much detail for me before. Even an electrical idiot like me can do what you've described....I'll let you know what happens,probably Sunday eve or Monday...Cheers again, Chris.

[CHRISZZR600]

Thanks to the info supplied by 416 and a few other tests it was found to be the reg/rectifier box. Second hand one fitted and it works like a dream.14.2 volts across the battery with everything running. Many thanks to all who replied with ideas. Chris.

[416cc]

Thank you for letting us know the outcome.

Happy riding.