Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > 916 alternator/regulator

[mat2hew]

I've got a 1997 916bip, I bought it about 2 years ago, I was told that it had had a new japanese regulator fitted. After about 1 month it stopped charging and I bought a new regulator (RR51) and fitted it, no problem, But in october this year it stopped charging again, I touched the regulator and it was red hot (hot enough to burn my fingers) so I ordered another (RR51) Sadly I have only just got around to fitting it, But no joy, still not charging and the new one gets really hot as well, I tested the output and it's only 8.5 Volts, I have tested the alternator output and that puts out about 80 volts AC at 6000 rpm, Any body know whats wrong?

[Shazaam!]

You need to replace the stator wires from the engine cover to the connection to the regulator. Better still, relocate the regulator for better cooling.

Here's the full story:

http://www.ducati-upnorth.com/tech/chargingfailure.php

[mat2hew]

Yes that may be the problem, I noticed that the yellow wires did look a bit worse for wear, Does that mean I should take off the alternator cover and solder new wires to the stator directly do you think, or just join them outside the cover? do you think that it could have damaged the stator its self (the're quite expensive), I guess I'll find out.

Thanks again, I've googled the problem but not found an article as helpful as that one.

Matt

[Shazaam!]

Just join them outside the cover. They stay separated inside the cover so even if you have heat-damaged insulation they can't short together in that area. Shorting together inside the sheath will often damage the regulator/rectifier but usually not hurt the stator windings.

[mat2hew]

Thanks, I'll Do that This afternoon, I'll Let you know the outcome.

[tonto67]

Originally Posted by mat2hew

Thanks, I'll Do that This afternoon, I'll Let you know the outcome.

How did this work out for ya?
I have the same problem. I'm on my third RR in 2 years. I relocated the last one as per Shazaam's recommendation. However just realised she aint charging again. Done the un-regulated voltage test and got 80V @ 6k RPM.I'll replace the wire with heavier stuff. Is it likely this is after taking out another RR?

Ok well I cut the alternator wires back to within a couple of inches of where they exit the engine case the wire looks in good condition. I took an ACV reading from there and got the same 80 ACV @6K RPM. Thats 60V short of where its supposed to be. From this reading I have to assume the stator is faulty. Electrex do a replacement unit, anyone any experience with these? Im pretty sure the RR is dead aswell so gonna get em both from eletrex. Have a new Yuasa battery to go in too so hopefully it'll be the last time I have to strip this system down. Have also learned that I might have contributed to this failure by allowing my last battery to discharge. Then jump starting the bike and allowing the charging system to revive the battery. I have learned(thanks to Shazaam) that the single phase 350watt system is not really up to this. So from now on Its gonna be replace all wiring with 10guage, solder all connections, install a voltmeter, relocate the RR and pay special attention to my battery condition. If the battery dies i'll get the Odessy unit Shazaam recommends.