Charging System Upgrade Explained

[Chris71mach1]

ok folks, we've all heard the horror stories. battery dies. bike on the side of the road. charged the battery and it still dies. NEW battery and it still dies. (and so on, and so forth.) what it all boils down to is that Honda seems to not have designed the charging systems very well on a lot of their bikes, and from what i can tell, this holds espically true for VFR's. from our perspective, and since we love our bikes so much, THIS SUCKS! after having these problems myself, and doing plenty of research, reading up on this topic, and talking to a number of people who know a LOT more about these bikes than i do, I finally came to the conclusion(s) of repairing the bike myself with a few aftermarket tweaks.

this stuff is obviously best done when the r/r finally fails you, and you have to replace it altogether. thats not to say that any bike out there couldnt benefit from this thread, and who knows, it may even be a good idea to perform this upgrade on a bike that hasnt failed yet just for the sake of preventative maintainence.

okay, so here we go. the most common problem here seems to be that the r/r dies prematurely. (hell, my own bike is on at LEAST its third that i can tell). from what ive gathered, the reasons for this are:

(1) internal grounding. this causes the r/r to not be able send as much ground current out as it needs to, which generates unnecessary heat.

(2) poor air flow at or around the stock mounting location for the r/r. again, the enemy here is heat. these things get HOT, and it comes as no surprise that over time, they literally fry themselves.

(3) inadequate pathways for enough current to flow both to charge the battery, and for the standard ground wiring coming out of the r/r.

now, the fix. i'll address these in that same order.

(1) the internal grounding of the r/r is an issue. this is easily fixed though, as i simply found an example in the CBR r/r that a previous owner had used on my own bike. this mod is fairly easy, as it is really only adding one wire to the existing r/r, though you have to partially disassemble the male connector block on the *battery* side of the r/r wiring (the connector that has 4 blades in it). You will need a tiny little flathead screwdriver, a length of 20ga wire (id say about 6 inches), and an eyelet to put on the end of the new wire. as youre looking at the top of the connector (the side with the clip up) you will notice 2 red wires on the left, and 2 green wires on the right. the red are the hot leads that send current to the battery to help charge it back up, and the green wires are both grounds. the r/r that i have came with the external ground on the bottom right (the bottom green wire), so thats where i recommend putting this. youll want to use the tiny flat head screwdriver to go in the back of the connector block and push down the clip that holds that blade in place. carefully pull the blade out of the connector block. strip one end of your length of 20ga wire, and gently pry open the part of the connector blade thats holding the stock r/r wire on (it wont take much, the 20ga wire is pretty small). slide the stripped section of the 20ga wire into the blade crimp with the other wire, and use some pliers to crimp it back and secure it. next, just to make 100% sure this wont come apart, dab a small bead of solder down on that blade to hold things in place. now just re-insert the connector blade into the connector block, and install an eyelet on the other end of that 20ga wire. now, youve just modified your r/r to be externally grounded. I ran my external ground wire to my subframe and bolted it there, and it seems to work fine.

(2) that pesky air flow issue. this can be addressed in a number of ways. some folks relocate the r/r entirely, some find creative ways to duct air to the r/r. I got lucky, and was handed the following link:

http://homepage.ntlworld.com/stu.tyrrell/Turbo_Mod.htm

that howto just rocks. these pc fans are really cheap (i again got lucky and being a professional geek, i have a few of these sitting in a closet ready to be used for some wierd motorcycle hack job). the only creative things i had to figure out was where to run the wires, and i also had to modify (yea, by modify, i mean cut a little hole in) my rear fender so the r/r would mount in the stock position with the added bulk of the fan on it. i ended up running the ground wire for this fan to the external r/r ground on my subframe, and i splice the hot lead for the fan into the hot lead for the license plate light on my bike. this way, the r/r fan will come on anytime you turn the ignition on, and will turn off when you shut your bike down. no ducting, no relocating stuff, and its a win/win!

(3) the main part of the charging system upgrade. extra wiring. this is the fun part. though one thing i have to say, to you folks who are afraid of doing electrical work like i am, dont be scared! this is easier than it sounds once you sit down and start work!

basically, ill start by showing you 2 wiring diagrams. one is of the stock r/r configuration, and the other shows a diagram of the r/r wiring with the charging upgrades done to it:

vfrstock.jpg

vfrmod.jpg

now here are the tools/materials I used for this: several feet of 12ga wire (youll want to have at least 10 feet handy), wire crimps (unless you want to solder the in-line wiring and use heat shrink tubing), those handy blue wire splice things (i forget what theyre called, but you could also use the button-hook method for wire splicing in this case), needle nose pliers, 4 eyelets to fit on 12ga wire, wire strippers, a roll of electrical tape, 2 inline fuse holders (12ga wire on them of course), and two 10 amp fuses to put in the inline holders.

I started with the ground wires, cause theyre the easiest. first, youll want to cut the jacket off of the small wiring harness that comes out of the r/r to go to the battery (this is the jacket around 4 wires...2 red and 2 green). pull out 2 lengths of 12ga wire that will run from the r/r to the negative battery post (yea i know the diagram says to use the frame ground, but i just opted to run these to the battery). make sure you run enough slack to tuck them in or run them around stuff to your own liking. this will look as good or as bad as you want it to. use your blue crimp splice thingys to splice each new length of 12ga wire onto one green wire each. on the other end of these wires, strip the end and crimp on an eyelet. make sure the eyelet is big enough for the battery cable bolt to go through (i had to drill my eyelets out just a little for this to happen). okay, so that was pretty easy. wham, bam, thank you viffer. so cool, now onto the positive charge wires. the lengths of 12ga wire you want to run now are going to be somewhat shorter. only run them halfway across the frame. now take your wire crimps and strip one end of each wire, and crimp on a fuse holder to each one. on the other end of these, use a couple of blue splice crimp things to splice each of these into the 2 red wires on the r/r. this is where youll want to move over to the right side of the bike to finish this. now, run 2 more lengths of 12ga wire that will run from the inline fuse holders to the positive battery terminal. strip BOTH ends of these 2 wires. each one will crimp to the fuse holder on one end, and to an eyelet on the other. bolt the eyelets to the positive battery terminal.

well...ok....thats really about it. itll likely take you as long to read this thread as it will to do the majority of this work, but hopefully this thread can consolidate all the research ive done into a quick place for other vfr owners to find all this useful info.

another thing that i ran into during this repair was the fact that the female side of the connector from my r/r to my stator was absolutely fried. i implore yall that if yall see burnt, damaged, or outright fried wiring, to just replace stuff. I went to my local Honda dealer (Honda West, at the weatherford traffic circle for you guys in DFW), and they just GAVE me the female connector block and 3 blades. i built the connector with some wires, cut the old one off the stator wiring, and crimped the new one on. an easy fix, cheap as hell, and i dont have to worry about running damaged wiring anymore.

[Guest fatso127]

Chris this is by far one of the best write up for the R/R problem i have read. real clear and concise...thanks man. this should be shared with other vfr sites....just my 2 cents.

[Tightwad]

Or you buy the Harness I made that does exactly this, but with 8 gauge Positive wires and no crimping into the existing charge wires....

Nice writeup, although there is a pinned version that is pretty much the same (and where my idea came from, I am not a genius). The key issue to remember is that the connections are only as good as you make them right now....they degrade so if you use tape to cover it will come undone in the heat. If you solder too cold it will look like hell and perform no better.

Don't be afraid of electrical, it's just a simple minded puzzle with fun tools.

[Chris71mach1]

that harness kinda worries me....it doesnt address the internal grounding problem of the r/r at all, nor does it have any fuses built into it that i can see. it looks great and would prevent one from splicing into wires (hence making it easily removable and easy to return the bike to stock), but how about the air flow issue?

that harness is a great start, but not quite comprehensive. (nor do i see anything geared to the older bikes, either)