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Discussion Starter · #1 ·
I have a 1993 888SPO. The charging light came on. Chucked the battery for a new Motobatt. Also swapped out the regulator/rectifier for a new one. Finally, the jump harness from the alternator to the r/r was melted in a bunch of places (!??!!) so I built a new one using 10 gauge wire. With all these changes the light is still on, but very dim and it goes out when I'm running at 4500rpm. Progress, but not solved.

At idle the battery reads at 13.19--down from the 13.48 when fresh off the charger. The techs tell me I should be at 14.2 when running. Blah.

I seem to recall reading about some relation between charging and the kick stand down sensor. Does anyone know what it is--or am I making it up in my head? Figured I'd ask before I go back to the r/r. Thanks.
 

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I think your next step is to check your stator. Good luck finding the issue.
 

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Matt
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That's a damn good post. Read it off the 851/888 forum. If you wrote it, well done sir. And a heck of a collection of bikes you got there too. Where in Michigan?
Credit to Brad as xracer noted. I ran into the same problem and someone eventually posted that link to Brad's write-up...it's the most comprehensive that I've seen to date.
 

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Brad's procedure is second to none, he's a very accomplished mechanic and does the bread and butter stuff very, very well.

My 888 with it's single phase charging system is only just capable, it's ok on a carbed bike but injected bikes really suffer from the fluctuation in voltage, particularly at idle or just above.
I'm in my 20th year of ownership and i reckon i've "solved" my issues, it used to chew through RR's very regularly, obviously i made sure the basics were ok but from there i did the following

upgraded my main starter wires, Cu flex, as large as i could fit, to make the startup process as fast and efficient as possible
Added earths and checked all of them, i earthed the RR and applied dielectric grease to all connections
Use a battery tender, keeping the battery voltage constant when not being ridden (and mine doesn't get out as often as i'd like) is key to helping a marginal system cope.

And don't overload the system with nonsense like GPS or phone charge points, heated grips etc, they will just help in keeping your battery voltage low.
The additional earths fixed my dim charge light issue and i haven't had a RR fail since doing it either, the other tip i can give is to make sure your two yellow wires are connected securely with clean new terminals or plug.
 

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+1

do not expect much better than what you are getting as it is not the same charging system as a 1998 and later bike. you have 350watts vs 550 IIRC. I would be happy with 13.19 at idle, you should see it hold steady at that voltage and start to climb as you get closer to 2000 rpm's with the regulator kicking in around there so no higher than max.

What rectifier did you choose to replace the oem with? this may be your charge light issue, the factory updated version deleted the light function but was reliable so a fair trade. My 92 851 went through 3 oem ducati electronica rectifiers before I installed the oem hitachi and never had an issue since. Bottom line if the bike is charging (and it seems it is) but the light is funny I would check with the company who sells the rectifier as it may not be right.

there used to be a belief that a clogged fuel filter would tax the system enough to cause a failure, I am not sure it would but something to think about.
 

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Discussion Starter · #10 · (Edited)
Thanks much. When I bought the bike it had an aftermarket r/r from some supplier in Holland. I swapped it out for a stock Ducati with light function. It was on that unit that the light started coming on--after riding with no light for 100's of miles. Swapped out r/r for a unit from some outfit in Quebec/changed battery/built harness. I'm going back to the original r/r and see what happens.

Changed fuel filter in last 1,000 miles.

Anyone have a source for those giant size bullet connectors the yellow wires on old style r/r's use?
 

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Maybe you shouldn’t fix it unless it’s broken.
 

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Don't use those big bullet connectors, they are/were the cause of most of the charging issues on the single phase alternators. The female part of the connector spreads easily with the heat [ snicker,snicker] generated by the high demand/resistance and they burn. Many people solder the wires together and insulate well. There are some connectors that screw together [used on trailer connections] that work well too. There are big spade and bullet connectors out there but they need to be a very tight fit together and have a large enough contact area to handle the current generated.
 

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I would only use the bullets for that job. Same size as original and heat shrink- they’re very reliable ime. I buy them from Wurth.
 

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Solder is the most efficient. No resistance so no heat. It’s just as easy as stripping and crimping and more reliable.
 

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HTML:
Thanks man. Hope you're enjoying the winter.
Don’t worry, I’ll be there soon. I was just waiting for Christmas with the family. :wink2:
 
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