Hi all, been looking at a charging problem on my mates 97 748. I've done various searches following our findings but need a little help. We know from research that we should be getting somewhere around 70volts on each wire? As a maximum output? Is this correct ( I do mean volts not amps). We have some very squishy wires and they look to me like they need cutting back and new connectors put on, but when running and revving we are getting around 5v out of each wire and when u rev the bike harder the output actually drops to around 4.06 ish on each one. Before we strip, does anyone else want to confirm my suspicion that the alternator is screwed because it would still be putting out more voltage even with slightly average wires?
Hi,you should be getting 35v ish at1500rpm increasing to 70 at 3000,then 140 at 6000.Dont forget its AC and measured across the two yellow wires.
Hi, thanks, sounds like we were measuring wrong, we were measuring DC from each yellow wire to the negative on battery! So we need to measure AC with a voltmeter between the two yellow wires? Anyone got any recommendations on whether u can just replace the stator with another aftermarket 2 phase? Or how easy is it to change to 3 wire (phase) do u need a new flywheel etc? Or literally just the stator.
Did yours just burn out then to a point where it wasn't outputting enough power? Tbh we aren't keen on taking the engine cover off, seems like a big job!
Do your checks first, its more common for the reg/rec to pack up. Poor connections will effect charging, eliminate as many connections as possible. Steve
After burning a couple of RR's I just had no confidence in it. So i had it rewound and larger rated yellow wires installed. I am sure it was giving me spikes and burning out my RR's. Its been fine since. The casing isn't too hard to remove once you have one of these Laser Tools 5334 Motorcycle - Alternator Cover Puller Ducati Tool Garage Auto | eBay I didn't. But I fashioned one out of a part of handlebar mirror clamps I had lying around from a GS750. Its dead easy to remove with the correct tool. Its not that big a job.
Yep. It's been bodged and has 2 sets of crap bullet connectors so we are going to re-wire some of it, the reg rec wiring is all going to be cleaned up but the connector looks ok
And thanks guys , much appreciated, are bullet connectors okay if they are rated for enough load or shall we use blocks? We are going to need 2 joints though as it's been hacked
As Birdie says, the RR is a common fault. Regulator Rectifier for DUCATI CAGIVA LAVERDA 350SS 400SS 600SS750SS 900SS 500 PANTAH 600 750 900 MONSTER 748 750F1 manufactured by Electrex World | Electrex World Ltd for replacement. Note: do not use bullet connectors between yellow wires from stator to RR. Always solder them and use good insulation covers. The connectors can get very hot as they have a high resistance. Causing a burn out on the wire.
Hi Guys, been looking around for wire for the bike; can anyone tell me how big 10 Gauge is compared to the standard stuff coming out the alternator? do you recommend 10 Gauge? I have read quite a few posts where people have done this. Our Plan is to strip back to maybe 3 inches in from where the cable goes into the engine, solder in 2x 10 Gauge and then run in up over the engine as before but then solder it again as close to the Reg/Rec as we can. we will have 2 joins but they will be solder and not bullet connectors as they are now. Does that sound like a plan? Also can you confirm that to measure output on the Alternator we need to be testing each lead at a time with the negative for the Multimeter on the batter Negative terminal? From our testing at the weekend it was clear that we have 12.7Volt in the battery and when idling and blipping the throttle it doesn't go up to 13V; so it isn't charging. I don't think the Reg/Rec has failed but we won't know until we are getting good output on the alternator.
Without wishing to sound like a knob end..... There's a really good detailed section in the haynes manual on the charging system. I have a two phase reg/rec you can have for £25 delivered if your mate wants it.
I appreciate that, thanks Nelson I'll give you a shout if we don't get it sorted as I don't wanna take engine covers off it. I agree, the Haynes manual would be a good shout, but again it's his bike, I am just trying to help him out, will recommend he gets one ordered up.
if you have time, the charging problems are the subject of many threads on here - e.g. :- http://ducatiforum.co.uk/f41/why-reg-recs-notorious-weak-spot-14197/
Hi, so a bit of an update. Cleaned all reg/rec connections and stripped back stator wires about 2 inches and soldered directly to the reg rec wires. We now get 13.9v at around 2000 rpm and around 12.9v on idle. However the voltage is still dropping right away to low 12v's when u dial in more revs. So.... Stator burned out? I have read tons of posts now, thinking about getting Nelson's stator and getting it re-wound and then fitting it. Any thoughts?
get it rewound, they'll put thicker wire on too. Buy a new RR. Then forget all about it. I did and have. Its just not worth the hassle. Honestly its simple to remove the casing and remove the stator. As long as you have that puller. Just need gasket and oil.
Phil Have you measured the A.C output across the 2 yellow wires Without anything else connected? This should be your first test. As Keith916 mentioned you should see you 35v ish at1500rpm increasing to 70 at 3000,then 140 at 6000. approx. If you ain't getting something in this range without anything else connected you have a problem with the alternator. If you are getting something like these reading Without anything else connected then the problem is 'upstream' of the alternator and you should then suspect regulator/rectifier/bad connectors/something tracking through to earth?
I will bet it's the reg/rec breaking down under load. Steve Ps check your stator before striping it down and wasting time and money.
Umm no, 2 reasons! Wasn't sure what setting I needed the multimeter on (please don't laugh) as I am used to doing DC. Do u need to measure across the two wires? Ie yellow to yellow? We have ordered a Haynes manual also.
