[fergy]

I'm posting this here since my personal web page hosting has gone away...



Relocating the Regulator/Rectifier from
over the Goat's Belly, to frame for
better air flow.

The Regulator/Rectifier (R/R) is mounted from the factory to the bottom of the battery box, right above the pre muffler, or Goat's Belly, where it gets an enormous amount of heat. The r/r generates it's own heat by converting AC voltage to DC voltage and that added to the "cooking" it gets from the Goat's Belly, is enough to eventually cause it to fail. It could, (although I haven't seen proof of this) cause your stator to fail at the same time. So, one of the first mods we 750 owners should do, is move the r/r to a cooler location.

I have my own way of doing this, which in my opinion was much easier than to remove everything from the battery box and lift it up to reach the bolts that are coming up from the r/r and are screwed into nuts that are spot welded into the bottom of the battery box. My method is to drill out the bolts from the top.

Tools needed:

Drill with extension bit
Pilot bit
1/2" drill bit
1 1/8" U bolt
1/4-20 Lock nuts (4)
1/4-20 1" bolts (2)
1.25" piece of 3/8" fuel hose
piece of strap metal to use as new mounting bracket

Start by removing the seat and battery. Then remove the rubber pad in the bottom of the battery box.

You can see the nuts where they are spot welded in the bottom of the battery box. Using a center punch, mark a dimple in the center of each bolt, then use the pilot bit, (I used a 1/4" pilot bit just to make a center hole in the bolt) to make a pilot hole in the center of the bolt with the drill. Then use a 1/2" bit to drill out the bolt. It will take the nut with it down to a nub. You will hear the bolt fall down when you are far enough, and the r/r will be free.

Here's a nice blurry pic of the bolts/nuts. I shot this in the dark with a flashlight so the camera had a hard time focusing. I drilled them out and left it for finishing in the morning.

Here's a pic of the finished drilled out nuts I shot the next morning before I put the battery back in. I used a telescoping magnet to pick up all the metal shavings.

U-bolt (A) with piece of fuel hose (B) used to protect the frame, and the piece of strap metal (C) I used to mount the r/r in it's new location, right above the left passenger foot peg. I marked the holes for the u-bolt and the r/r, and used a drill bit one size larger than 1/4" to drill the holes. I used lock nuts with washers on the ubolt and the bolts holding the r/r onto the mount. Notice that I mounted the u-bolt above the grommet where the side cover snaps in. I also used dielectric grease on the connector pins before I plugged it in to the r/r. That's it, r/r relocated!

NOTE: If you are having charging issues with your bike, you should go through this Electrical Fault Finding Flow Chart and find/fix the problem before doing any mod! http://www.electrosport.com/media/pdf/fault-finding-diagram.pdf

 

[slimvulcanrider]

Good write up... Sticky please!!!

 

[clock152]

Thanks Bro

 

[The DEUCE]

I did the exact same except I used a 3/4" Electrical Mineralac Strap and painted it black.

 

[fergy]

Good input! Always nice to have more options.

 

[Puck]

Thanks for the info. I did this last week and it worked great! I had previously replaced the rectifier twice and not one mechanic at either shop I went to had the sense to suggest this.:smiley_th

 

[Kayakrazy]

Problem dry fitting R/R relo

Hey Fergy and The Duece

I bought the hardware to do both of your relo's to see which I liked better. But dry fitting both I found I couldn't get my side cover back on without notching it out. My bike was hit from behind in it's former life so I don't know if that distorted the frame and changed the clearance tolerances or what. I've looked at both your pictures and your side covers don't looked notched to me.

How'd you get your covers back on? Ya think my frame's slightly bent? Seems to drive okay. Just curious, George.

 

[fergy]

I would be guessing without a photo, but unless you used a much thicker U bolt, mine fit with a tiny bit of room to spare without having to notch out the cover.

 

[The Admiral]

Kudoes to Fergy and Duece

Did the R/R mod yesterday. Removed the rear gaurd to get to the bolts which actually came off without a hitch. Modded the dueceman's set up adding a bracket with a 90 in it and mounted. Drilled the shield for clearance with the wire harness. Thru on a little paint and wholla...

 

[The DEUCE]

Hey Fergy and The Duece

I bought the hardware to do both of your relo's to see which I liked better. But dry fitting both I found I couldn't get my side cover back on without notching it out. My bike was hit from behind in it's former life so I don't know if that distorted the frame and changed the clearance tolerances or what. I've looked at both your pictures and your side covers don't looked notched to me.

How'd you get your covers back on? Ya think my frame's slightly bent? Seems to drive okay. Just curious, George.

I had to notch my cover and it is not noticeable at any angle.

 

[eusjma]

Just a general question about either method:

How 'stable' is the RR after the move? Hard to tell but I was wondering if the thing vibrates a lot while the bike is running

Jeff

 

[Ndr]

Just a general question about either method:

How 'stable' is the RR after the move? Hard to tell but I was wondering if the thing vibrates a lot while the bike is running

Jeff

Along those lines of questioning, how prone is it in this location to get nice and wet on a rainy day ride? Will the excess water damage the circuitry in the R/R?

 

[slimvulcanrider]

i have had mine located there fore 3 years... no damage at all.. no bad vibrations either

 

[fergy]

The mount I did was very solid, no wobble or vibration at all. And, as far as the moisture, it is a good idea to use dielectric grease on the connection so that you keep it from gathering water and corroding. (on all connections on the bike for that matter) If you're riding in weather, there's no way to keep the r/r dry, no matter where it is located, so even if you don't relocate it, it is a good idea to seal the connector with dielectric grease.

 

[TuxedoSeven]

Along those lines of questioning, how prone is it in this location to get nice and wet on a rainy day ride? Will the excess water damage the circuitry in the R/R?

The electro sport I used came with a wire harness instead of the OEM style plug.
I snipped off the plug then soldered and shrink wrapped the connections on that and the stator. So far, no worries.

 

[VN750Rider/Jerry]

I have put almost exactly 150,000 miles on 2 Vulcan 750s, never relocated the R/R, and never had one fail. That doesn't mean one won't, but I doubt moving it will help.

I never really understood how the charging system on motorcycles worked, because I had never had any problems with them. When I got my '85 Goldwing, I got a crash course in motorcycle charging systems. The Goldwing has one of the worst. It uses the same design as the Vulcan, but the stator puts out a lot more power, 500 watts in the case of my 1200LTD. I quickly discovered the difference between a motorcycle charging system and a car charging system. On a car, the alternator output is controlled by load, the more load you place on the system the greater the alternators output, up to it's limit.

A motorcycle charging system is COMPLETELY different. It does not use a controlled output. It runs wide open all the time, at full output above a certain rpm, no matter how much of that current is actually being used. Now comes the really dumb part. Part of the job of the R/R is to convert the AC current from the stator to DC, so the bike can use it. The other part is to "dump" unused current. It does this by shorting it directly to ground. Now of course this develops a lot of resistance in the R/R, which causes heat. In other words, the R/R works just like an electrical heating element, like the burners on an electric range. The difference is, with a heating element, heat is the desired result. With the R/R it is not. It is simply an undesired side effect of the way an R/R works.

On bikes that use almost all the current the stator puts out, it really isn't that much of a problem. The R/R will get warm, but that is why it has fins on it. It is basically a heat sink. The heat coming from the goats belly is really insignificant compared to the heat generated inside the R/R. And it is only there when the bike is not moving. Once you start riding, air blowing over it carries away most of the heat.

My Goldwing was a different story. First of all the 500 watt stator was totally unnecessary to run the bike, and was probably put there because most Goldwing owners add all kinds of electrical accessories. I didn't. I figure it takes less than 200 watts to operate everything on the bike, leaving at least 300 watts to be disposed of. Then Honda used an R/R that lacked anywhere near the capacity to dump that much current, and mounted it under the fake gas tank, where it got no cooling air at all. My system had three white plastic "molex" connectors between the stator and R/R. All 3 were fried. I cut them out, and soldered everything together, trying to eliminate as much resistance as possible. The R/R still got hot enough to actually set the bike on fire (it set fire to the insulation of some wires that were in contact with the fins) Fortunately this happened while the bike was idling, with the fake tank off, while I was working n it, and I quickly got the fire put out. I repaired the damage, but realized that this was simply not going to work. Even if I kept everything away from it, the internal heat would eventually cook it. My solution was to mount a high output blower type fan under the fake tank (there was plenty of room under there after I removed the cruise control, on board air compressor/self leveling system, stereo amp, and trip computer) which drew about 5 amps, removing that load from the R/R, and running a duct from the blower directly to the R/R, which blew a LOT of air directly on the R/R. I have put over 2000 miles on this setup, including one 600 mile trip, and nothing has failed. I carry an extra known good R/R with me just in case.

So while relocating the R/R on the Vulcan shouldn't hurt anything (as long as you don't cut any wires) IMO it really won't help either. Your bike your choice.

 

[denny6006]

Having trouble following the logic. Heat doesn't cause electronic failure ? Goat's belly not that hot ? Blower is good but relocating to a cooler location is a waste of time ?

Lots of R/Rs fail. I'm glad yours didn't. Clean up the connectors. Solder and shrink wrap them if you have some time to kill. Moving it to a cooler location is fast, easy and not a bad idea.

I see you hadn't met Jerry,we may not always agree and his line of thinking is a little different ,but he is straight up and says what he thinks.You never have to wonder where he stands on any particular subject.I had missed him

 

[VN750Rider/Jerry]

Having trouble following the logic. Heat doesn't cause electronic failure ? Goat's belly not that hot ? Blower is good but relocating to a cooler location is a waste of time ?

Lots of R/Rs fail. I'm glad yours didn't. Clean up the connectors. Solder and shrink wrap them if you have some time to kill. Moving it to a cooler location is fast, easy and not a bad idea.

First of all, I don't consider the Vulcan's R/R to be an electronic device, because it does not contain anything digital. To me it is an electrical device. On my Vulcan I did remove the 3 connectors in the stator wires, and soldered them together, because I found heat damage to the wires around the connectors, and in an electrical circuit, heat means resistance. My guess was the connectors were not making good electrical contact, creating high resistance, and damaging the wires near the connectors. I have not noticed a problem since, and that was maybe 30,000 miles ago.

It is the job of an R/R on a motorcycle to generate heat. It shorts excess current to ground, creating heat in the process, just like a resistance heating element. That's why it has fins on it. It was designed to get hot.

I agree that excess heat will usually shorten the life of most electrical components, but in the case of the R/R, it is likely to be internally generated heat that does it in. Virtually all electrical parts that generate heat will eventually burn out, whether it is a light bulb, a fuse, or a heating element. Heat slowly changes the molecular structure of the metal, and resistance goes up. Eventually it reaches the point where it gets hot enough to burn into. I do not believe the "goats belly" makes enough heat to cause any damage to the R/R, because for one, it is external heat, and two, the R/R makes a lot more heat internally than what comes from the exhaust.


But, I also don't believe you are going to do any harm by relocating it, as long as you don't cut wires. When you cut and splice wires, you create the possibility of a bad connection, which has high resistance, or a "hot spot", which would definitely be likely to cause more damage than the exhaust. Some people have spliced in enough wire to move the thing all the way to the front forks. I have not relocated mine for two reasons, I don't believe it is necessary, and I don't like the way it looks on the outside like that. If protecting it from heat is the idea, it seems that a cleaner solution would be to install some kind of insulation between it and the exhaust.


The Goldwing issue is an extreme example of poor engineering, with no good solution. Many people have spent hundreds of $$$ converting their bikes to a belt driven car alternator, driven from a pulley bolted to the front end of the crankshaft. Something like that, done in a neater way, is how I think it should have been done in the first place. Nobody who has done it that way has ever complained of any problems since doing it. When Honda came out with the 1500 six cylinder Goldwing, it DID come with a load controlled automotive style alternator.

 

[AZ Kev]

I have a question about relocating the R/R : does it create any kind of issue for a passenger? Looks like it would end up being under someone's left leg after the remount - does it get hot enough to burn the passenger's leg or cause other discomfort/issues?

Just curious : )


AZ Kev

 

[Knifemaker]

I have a question about relocating the R/R : does it create any kind of issue for a passenger? Looks like it would end up being under someone's left leg after the remount - does it get hot enough to burn the passenger's leg or cause other discomfort/issues?
AZ Kev

Only if they are wearing shorts and flip-flops..........