'95 M900 rectifier replacement?

[MonsterGrrl]

Hi all,

I've been experiencing problems with my (carburated) '95 M900. I believe it needs a new rectifier, as the one that's been on the bike for at least the past 5 years started smoking heavily. The bike blew its ignition fuse (7.5 amp) so I replaced it with a spare. The bike started up again, and when I put it into first gear, it died. Turns out I blew the spare fuse, too. I replaced the 7.5 amp fuse with a 10 amp fuse, and the bike started up, but then the rectifier started smoking terribly, so I turned the bike off, and have since removed the rectifier.

Obviously, it's out of warranty, so I'm on my own sorting out this problem. I have some experience working on my own bike, but it's always been under the direction and/or supervision of far more mechanically experienced people, so please be patient with me. I'm working on a very tight budget, so taking the bike in to the dealer is not my first choice, if I can help it.

I called the local Ducati shop, who quoted me over $300 for the part, stating that the new rectifier/regulator is made for the sport bikes ($150), and requires an adaptor ($200?) to make it work for the Monster. I found other rectifiers online specifically for the Monster (though not official Ducati parts) for closer to $140. Can anyone tell me their experience with using one vs. the other? Is it worth the extra money to purchase the Ducati approved part?

Thanks all for your input.

Cheers,
Julia

[Norm]

You should be able to find a used one on Ebay for $50-100. It doesn't matter what year or if it's 3 or 2 phase (just leave one wire unhooked if it's a newer 3 phase). Mount it, plug everything in and go. Wire the hot directly to the battery with a 30 amp inline fuse.
If you need more help, email me at: motomaxy@yahoo.com

[MonsterGrrl]

Meaning... the newer regulators are 3 phase, with an extra plug? So the more expensive option offers an adaptor for this extra plug?

I'm just wondering what the benefits are of this newer version, and if it's worth the extra money. Wouldn't buying a used regulator only guarantee this problem will arise again, only in a shorter amount of time, as it's a used piece? I'm curious about other people's experience with their regulator/rectifiers (and replacements) and what advantages and disadvantages there are in each version of this particular part.

Thanks for your input. Does anyone else have feedback for this topic?

[Norm]

No real advantage to either unit, you have a 2 phase so you'll ignore the 3rd yellow. If you can mount the unit in clean air, it will last almost indefinately. Heat is the enemy.

[MingThe Merciless]

I'm surprised at the price quote you received. My '99 M750 overheated its regulator/
rectifier last month, and all calls to various Ducati dealers quoted about the same
price of $140 for a stock OEM unit. If that's too rich for your blood, there are other
options available. Looking in the current Dennis Kirk catalog, an aftermarket unit
for your bike is $114. Still not the steal of lifetime perhaps, but a savings none the
less. And as for quality, I wouldn't hesitate for a moment. It's been my hard-earned
experience in life that aftermarket stuff is usually equal to OEM, and often better.
As for buying a used one on eBay (or elsewhere). How do you know what you're
getting? Used electronic stuff is a crap shoot of the first rank. Give it a wide berth,

[MingThe Merciless]

Originally Posted by Norm

No real advantage to either unit, you have a 2 phase so you'll ignore the 3rd yellow. If you can mount the unit in clean air, it will last almost indefinately. Heat is the enemy.

I saw your response and couldn't resist a comment. Forward mounting
of the regulator/rectifier is not always the answer to a maiden's prayers.
My M750 has a forward mount just under the headstock, but that didn't
prevent it from overheating and shorting out. Stop and go city traffic in
the heat of summer will make a mockery of wherever the unit is mounted.
My regulator got so hot it partially melted the epoxy filler material on
the back. Determined to have the last laugh, I've been toying with
mounting a small low-amp cooling fan over it. The local electronic
closeout store have tons of various sizes for $5 each. If nothing else, it'd
be a source of amusement to friends and strangers alike.

[Norm]

The connectors for the yellow wires are also a common problem, many people hard wire them. If yours feel very hot, redo them.
I mount my units in the front, in clean air, take off the heat sink, and space them off the frame about 1/4".