Installed a heatsink for the R/R
#1
Installed a heatsink for the R/R
I have had this idea in my head for awhile, I decided to implement it.
Took me about 10 hours over two days. My last R/R overheated and failed, taking out a phase of the alternator and killing the battery.
I wanted to purchase a MOSFET type R/R at the time, but they were sold out everywhere I looked.
It is now middle of summer here in Florida and where I live the road temps while in traffic can easily go 100F+. And not wanting the $400+ in parts to fail again, I decided to improve its cooling.
While I was in there, I decided to remove the brittle and burnt OEM connector. I used some side-cutters to cut away a majority of the black plastic that made up the female part of the connection.
I then filed down the rest to make it flush. I soldered some 16 gauge wire for the 3 phases of the alternator, the two field coil wires and the positive of the rectified voltage.
I took a look at the green ground wire that goes between the bolt and body of the R/R. The OEM crimp was in good shape, but a crimp does not make for a good electrical connection, so I flowed some solder in and around it.
Voltage at an idle of 950 RPM was around 11.4. It is now at 12.2. Also the voltage would peak at 14.9 at 3500 RPM it is now peaking at 14.9 at 2500.
This tells me that the OEM connector had a fair amount of resistance to it.
I also removed the connector down by the alternator, as it was also burnt and had a resistance of .6 ohms. After soldering the three yellow wires the resistance is .0 ohms.
Here is a link to pictures of the fabrication: RR Heatsink Photos by Jl4zio | Photobucket
I will be installing a fan next, so an update is sure to follow!
Took me about 10 hours over two days. My last R/R overheated and failed, taking out a phase of the alternator and killing the battery.
I wanted to purchase a MOSFET type R/R at the time, but they were sold out everywhere I looked.
It is now middle of summer here in Florida and where I live the road temps while in traffic can easily go 100F+. And not wanting the $400+ in parts to fail again, I decided to improve its cooling.
While I was in there, I decided to remove the brittle and burnt OEM connector. I used some side-cutters to cut away a majority of the black plastic that made up the female part of the connection.
I then filed down the rest to make it flush. I soldered some 16 gauge wire for the 3 phases of the alternator, the two field coil wires and the positive of the rectified voltage.
I took a look at the green ground wire that goes between the bolt and body of the R/R. The OEM crimp was in good shape, but a crimp does not make for a good electrical connection, so I flowed some solder in and around it.
Voltage at an idle of 950 RPM was around 11.4. It is now at 12.2. Also the voltage would peak at 14.9 at 3500 RPM it is now peaking at 14.9 at 2500.
This tells me that the OEM connector had a fair amount of resistance to it.
I also removed the connector down by the alternator, as it was also burnt and had a resistance of .6 ohms. After soldering the three yellow wires the resistance is .0 ohms.
Here is a link to pictures of the fabrication: RR Heatsink Photos by Jl4zio | Photobucket
I will be installing a fan next, so an update is sure to follow!
#2
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#5
the electrex unit starts charging at a lower RPM (under 2K?) than stock. Sounds like a new electrex or similar unit combined with cleaning up and soldering some of the factory connections and grounds as Jlaz has done would ultimately be the best solution!
#6
Join Date: Aug 2008
Location: Republic of Boon Island
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Further more fans or heatsink fins won't really cure an aging R/R with resistance issues and it could
still boil off a wet battery and mess up a gel or agm style one too. It's the one item I prefer to go
new with, right up there with tires, plugs, pads , filters and other "consumables" that wear out
still boil off a wet battery and mess up a gel or agm style one too. It's the one item I prefer to go
new with, right up there with tires, plugs, pads , filters and other "consumables" that wear out
#9
Regulator Rectifier fits HONDA CB750F2 CB750 NIGHTHAWK | Electrex World | Electrex World Ltd
Looks like they're currently out of stock, though. The electrosport is another good one but between the two of them it seems they're almost always out of stock- Gotta plan ahead and get one when they manufacture a batch!
#10
Melted insulation...
Kind of a follow-on to the original posting: has anyone else had the experience of the insulation on the wires at the R/R actually melting because the R/R got so hot? It happened to me on the weekend, a couple of the wires touched and the 10A ignition and starter fuse blew. Some dodgy roadside repairs got me home but I guess this means the R/R has had it.
Is this, er, "normal"?
Is this, er, "normal"?