Ducati.org forum banner
1 - 12 of 12 Posts

·
Registered
2001 S4 Monster, 2010 CRF450R
Joined
·
10 Posts
Discussion Starter · #1 ·
Hey all

What is your choice for replacing voltage regulator rectifiers on your Ducati?

I've seen unbranded Chinese options for my S4 for $25 on eBay, Whites brand for $130 and another more expensive Arrowhead brand for $250. I recall many years ago replacing one on a 916 and paid $400 for genuine option.

Anyone got any suggestions on options? Are the el cheapos junk and what about the mid range brands like Whites and Arrowhead?

Cheers
 

·
Registered
S4
Joined
·
55 Posts
Haven't had to do it to mine yet but after hearing the stories about fried wiring harnesses I will be putting a mosfet type one on mine when I finish my other project.
 

·
Registered
Joined
·
1,319 Posts
Haven't had to do it to mine yet but after hearing the stories about fried wiring harnesses I will be putting a mosfet type one on mine when I finish my other project.
171047


A MOSFET regulator/rectifier is more efficient and consequently will run cooler than a silicon controlled rectifier (SCR) but won't solve the common overheated connector issue. The connector between the stator and the rectifier has to carry a high (40 amp) current — so a small resistance caused by corrosion, or poor connection, will cause heat induced damage (crispy) to the connector and adjacent wiring.

The permanent solution is to eliminate the connector entirely by soldering the wires directly together — or to replace the connector with one more waterproof and having a more positive connection.

Here’s one solution.
171048

All owners should inspect the stock connector regularly for looseness and any discoloration indicating overheating.
 

·
Registered
2001 S4 Monster, 2010 CRF450R
Joined
·
10 Posts
Discussion Starter · #6 ·
Thanks for the replies, much appreciated and lots learned.

I wasn't aware of the mofset option but after some research have bought one for my S4. I live and ride in a hot area so any option to keep the electrics cooler is good I think. The unit I bought looks the same as the OEM model and was $70 with 12 month warranty. What connectors are on the model in your pic Shazaam!?

I've also ordered a pack of the Dryconn connectors. My last regulator rectifier had scorched connectors as well as resin swelling on the unit itself. I suspect it was the connector that failed first leading to failure of the regulator rectifier.
 

·
Registered
Joined
·
1,319 Posts
What connectors are on the model in your pic Shazaam!?
From an earlier post by owner spyvito:

171055


MOSFET Regulator Rectifier Wiring Harness

There’s a wiring harness from Triumph (Part No. T2500676) that plugs a Mosfet regulator/rectifier into the Ducati harness. The picture shows it attached to a ZX10R unit (Part No. FH010BA).

I got the Triumph cable and it is ALMOST plug and play. The 4-pin connector does not lock to the on-bike female connector. You could put a zip tie on it but if you are handy with tools, do what I did.

Using a precision screw driver, remove the male pins from the Triumph cable and your old r/r cable. Use the old connector housing, insert the male pins from the Triumph cable and you are good to go. spyvito
 

·
Registered
Joined
·
1,319 Posts
I live and ride in a hot area so any option to keep the electrics cooler is good I think.
My last regulator rectifier had scorched connectors as well as resin swelling on the unit itself. I suspect it was the connector that failed first leading to failure of the regulator rectifier.
Overheating of the regulator/rectifier (RR) itself is separate problem. A MOSFET will run cooler than an OEM unit but the mounting location of the RR is often the cause.
171056

The reason is that there is inadequate supply of cooling air inside the fairings and/or underseat areas where the RRs are commonly placed. The RR’s heat sink dissipates heat from the regulator's main transistor which acts as a variable resistor to ground for the excess current. So, whatever current is not being used for charging the battery and running the bikes electrical system is converted to heat. A lot of heat.

Keep it cool. Heat is the enemy of electrical components. I replaced my fifth failed regulator with an Electrex and moved it to a location outside of the fairing and into the air stream. I extended the wiring and mounted it on the underside of the license plate holder facing the rear tire where it’s hardly noticeable.

171057


All of my previous regulator failures were heat-related. Adding a cooling fan inside the fairing was tried but the ambient temperature in there is just too hot to use as cooling air. I even wrapped the front header pipe in high-temperature insulation (http://www.thermotec.com/tt/exhaust.html) to reduce exhaust pipe heat transfer in the fairing to a minimum but the regulator surface temperature still climbed well beyond 160 degrees at stoplights. The regulator itself generates a lot of heat itself so it prefers a cool location, preferably outside the fairing in the air stream. So far so good. The regulator still gets really hot while stopped, so it's no wonder that they fail when inside the fairing. If it's any consolation, Honda's do the same thing.
 

·
Registered
Joined
·
2 Posts
Hey all

What is your choice for replacing voltage regulator rectifiers on your Ducati?

I've seen unbranded Chinese options for my S4 for $25 on eBay, Whites brand for $130 and another more expensive Arrowhead brand for $250. I recall many years ago replacing one on a 916 and paid $400 for genuine option.

Anyone got any suggestions on options? Are the el cheapos junk and what about the mid range brands like Whites and Arrowhead?

Cheers
Rick's. Don't skimp.
 

·
Registered
Joined
·
48 Posts
choice of brand is widely debated. It would be nice to have a survey of which brands last longest, which models are prone to excessive heat, etc.
Take it at face value because that means the original OEM has previously failed. Otherwise, we wouldn't be here
 

·
Registered
Joined
·
2 Posts
From an earlier post by owner spyvito:

View attachment 171055


MOSFET Regulator Rectifier Wiring Harness

There’s a wiring harness from Triumph (Part No. T2500676) that plugs a Mosfet regulator/rectifier into the Ducati harness. The picture shows it attached to a ZX10R unit (Part No. FH010BA).

I got the Triumph cable and it is ALMOST plug and play. The 4-pin connector does not lock to the on-bike female connector. You could put a zip tie on it but if you are handy with tools, do what I did.

Using a precision screw driver, remove the male pins from the Triumph cable and your old r/r cable. Use the old connector housing, insert the male pins from the Triumph cable and you are good to go. spyvito
 

·
Registered
Joined
·
2 Posts
Triumph harness looks like a great solution. Do you know where the regulator is located on a 2018 Monster 1200S? Also does anyone know if Ducati is upgrading the regulators for the bikes with the Lithium batteries?
 
1 - 12 of 12 Posts
Top