No charge

[steve]

Hi there
can anybody explain how the charging system works on the monster, I am assuming the starter is a generator as well as a motor.
The motor startes ok with a good battery but there is no charging voltage from it when the motor is running.
Should the solonide re close when the motor is running.

Regards Steve

[carrot]

I've been having lots of fun with my charging system. Ok the generator 3 yellow wires from leftside of engine go into the rectifier funny looking ally thing with fins under airbox then 4 wires out of rectifier 2 x negitive 2 x positive check theres power from them should be around 13.5 volts if there is just trace wires until you find the fault. Bit of nightmare. :banghead:

[Nickj]

The starter motor isn't the alternator, the starter sits infront of the motor where it gets covered in carp.
The alternator isn't the startermotor, the alternator its tucked inside the engine casings over on the left side.
LOL I could tell you how they work but its just as easy not to know, doesn't help too much when they go fizz anyway.

[Nickj]

Check the connector where the wires from the alternator join the loom. They dump a lot of amps so a slightly dodgy connection can give you lots of problems.

[Scotty]

ahh you've got your wires crossed a bit here ( ba dum tisch , ahh that reminds me of the stand-up I did in an old people home , i was rubbish but they still pissed themselves)

err anyway

the starter motor does just that start the bike,
rather than have a meaty switch on the handelbars and associated meaty wireing theres a relay (that yellow or isit black box) makes the conection for you and the motor spins over

once the motor is running and you let go of the button the starter motor stops and the sprag clutch automatically disengage's it from the engine

the charging system is completely separate and on the left hand side of the crank there will be either 2 or 3 yellow wires coming out of the LH engine case near the front. 2 wires for single phase and 3 wires for 3 phase , 3 phase being more modern and betterererre)

these yellow wires go to the regulator/rectifier unit which is completely unfathomable and a bit of a mystery basically it turns the Alternating current from the alternator into a direct Current to charge the battery with, some of the other wires coming out of the alternator go to the battery

a basic check of the charging system is to measure the voltage of the battery with a multimeter (Maplins sell cheap as chips but good enough for this sort of thing if you don't have one) with the engine off it should be about 12.5 volts and with it running about 13.5 or something

its taken me so long to type all that i can see Ive been beaten in response time damm , so as above check the connections are clean and tight. the alternator to reg/rec unit connector is a classic point of failure on Ducatis in general

[Nickj]

But yours is better than mine Scotty.
CBR's had really cheesy connectors for the alternator, used to melt then take out the alternator and regulator.
Had the same on a 600SS, first I noticed was it sparking in the dark and charging problems. The connector was shot, as they carry 20 30 amps they have to be good as you noted

[bod]

"these yellow wires go to the regulator/rectifier unit which is completely unfathomable and a bit of a mystery basically it turns the Alternating current from the alternator into a direct Current to charge the battery with, some of the other wires coming out of the alternator go to the battery"

It works on the principle called a 'wheatstone bridge' using diodes to transfer AC to DC (sorry getting a bit geeky here)see below

http://www.allaboutcircuits.com/vol_1/chpt_8/10.html

[weenyleaper]

: But o my mates and ar my foes, It gives a super light

[Bunny]

"these yellow wires go to the regulator/rectifier unit which is completely unfathomable and a bit of a mystery basically it turns the Alternating current from the alternator into a direct Current to charge the battery with, some of the other wires coming out of the alternator go to the battery"

It works on the principle called a 'wheatstone bridge' using diodes to transfer AC to DC (sorry getting a bit geeky here)see below

http://www.allaboutcircuits.com/vol_1/chpt_8/10.html

or as the lad at college put it :
it changes bendy electric into straight electric so it fits in the battery !!!

[Trent]

or as the lad at college put it :
it changes bendy electric into straight electric so it fits in the battery !!!

:chuckle: :chuckle: :chuckle: Perfect description... Give the Lad an A+ !!

[stef]

The starter motor isn't the alternator, the starter sits infront of the motor where it gets covered in carp.


it's all a bit fishy..

[Shandy]

it's all a bit fishy..

Quality.....:chuckle: :chuckle:

The starter motor isn't the alternator, the starter sits infront of the motor where it gets covered in carp.

Are you Forest boys riding through lakes for fun now, is this what you do in the shin kicking off season??? (sorry can't resist a joke about the forest of dean)

[steve]

Hi Guys
All fixed now the two connectors running out of the regulator were full of corrosion, I useally clean the connectors every three months or so but I missed these two, got about 15.5v now. shouldnt have to push it now.
The starter regulator thing I remember being used on some of the old bikes but wont go into that (long time ago)

Regards Steve

[steve]

Hi guys
sorry to bring up an old subject, still not charging properly got a new regulator
but still goes flat after a few days. The three wires that come out of the crank case have about 30v AC on two of them and nothing on the third. I think this might be correct if the third is earth but not sure, have tried to get a circuit diagtam but they dont show the wiring of the generator.
any ideas would be helpfull

Regards Steve

[Sparky]

When the bike is running the voltage at the battery terminals should be between 13.5V and 14.8V, mine wanders between 14.5V and 14.7V. If the voltage when running is correct then the problem is either the battery, excessive drain on the battery when the bike is off or your journeys are too short to recharge the battery between starts.

By the way the measured ac voltage between any of the yellow wires should be the same as each wire is a separate phase so not grounded. You should only measure between yellow wires and not yellow wire to chassis.

Chris

[Nickj]

Thats where the two phase, three phase alternator bit comes in. There's some coils like motor windings which are where you get the wires from, one common joining one end of the coils and another set of wires off the other ends of the coils. Three wires in all makes it a two phase, four a three phase. Coming out of this is AC, a pretty sine wave flipping between + and - volts. The rectifier flips the -bits into +'s so you get a rough and ripply DC, the voltage regulator flattens out the ripples.
So if the rectifier/regulator is good you'll get up to 15V (and as many amps as needed up to the capacity of the regulator), if it's shot it can be less or more. More is when the battery boils itself to death.
BUT you can also get less when the coils or regulator are sick too AND either can collapse under load.

As hardy and stoical folk we take jokes about us in our stride, however the names of offenders are added to the notorious 'black book' maintained by the verderers court and the highly trained ninja suicide sheep are regularly updated with the surviving offenders names and details. So Shandy if you're over this way and you see a sheep looking hard it'll either be about to strike or even more worrying fancies you! :)

[retskcid]

Hopefully I have found what's caused my bike to be so unrealiable - it appears that it is not charging. Shows 13v on the meter, then down to about 9 or 10 when cranking, then back to 13v when running - no higher than when not running so must not be charging?

Now that I have established there appears to be no charge how do I test the regulator and alternator for fault? Obviously theres no charge from the reg otherwise would show more than 13v so start at alternator? Where/how can I get a reading from the alternator?

Thanks

Rich

*edit* having read the manual, you should disconnect the alternator (three yellow wires on my S4) from the loom and test using any two of the three wires coming out of it with the bike running - I'll come back with values (the manual quotes 2,000rpm and 6,000rpm values). 27v +/- 10 @ 2k rpm and 78v +/- 10 @ 6k rpm.

tested mine and it appears to be completely dead - no reading at all.

it appears that i had the meter set to dc and not ac! i'll have another go tomorrow. meanwhile, i checked continuity between the 3 yellow wires and all seems fine - with little or no resistance. sounds like if the voltage checks out tomorrow it may be the reg.

I rechecked the alternator and its fine, plenty of output. Now I have turned my attention to the regulator - the alternator wires and connector are getting very warm - but not sure how to be 100% sure that its the reg.