R/R straight to battery

Apologies if this has been asked and answered before. I am not entirely happy with my charge rate (13some volts with the lights on) and am thinking of running a wire straight from the R/R to the battery, with an in line fuse. My question is, do I actually cut the existing wire that comes out of the R/R or leave it connected anyway? In other words, does it serve any other function (powering ignition/coils ect) Hope I have made sense, thanks.

 

Compufire R/R install wrap - up on a 5th gen (finally) - Electrical - VFR Discussion

 

Thanks very much. I knew I had seen it somewhere, just couldn't remember where

 

Not sure what you are expecting to accomplish here...

There is already a wire that runs directly from the RR to the battery with an inline fuse--it's the 30 amp fuse on the starter relay. That fuse provides 2 functions so it would not be a good idea to bypass it unless you really know why and what you're doing.

Are you thinking that the resistance of that short piece of wire is causing a big voltage drop? i would suspect the spade lug connectors before the wire--sliding electrical contacts are not very robust or reliable, especially for AC voltage applications.

The voltage you measure at idle is determined by the net sum of the rectified stator output current minus the charging current for the battery, the normal operating load currents (headlights, ignition coils...), and any additional currents for loads you may have added (extra lights, sound system, etc). The stator and RR were never designed to provide full load output at idle speed-- hell the whole bike wasn't designed to just sit and idle for any length of time, it was made to ride!

 

Sorry, I should have made myself clearer, said charge rate was measured at 5000rpm. Thanks for the insight though. I recently changed the R/R on my Suzuki and that goes straight onto the starter relay via a fuse as you mentioned. Because wire on the VFR dissapears into the loom, and I have heard of that mod being done, I assumed it was taking a roundabout route back to the battery.

 

i had a '90 GS500e that was a blast to ride and nearly indestructible. i let a buddy ride it on a trip and he tossed it in a ditch going thru Deal's Gap--snapped the clutch lever, so i had to ride it home shifting without the clutch...it did great.

you probably know that a battery starts outgassing if the charge voltage gets above 14.4, so that's the upper limit on voltage out of the RR. How old is your battery and what's the voltage when it's at rest? If you are getting upper 13's at 5k that seems reasonable, fully charged battery voltage is 12.8. If your at rest voltage is lower than that then the RR voltage is being pulled down by charging the battery.

 

Yeah, the GS500's are magic bikes. My first road bike was a GS450, the whole family tried to kill that thing and failed! It finally came to a fiery end in the workshop (never run a bike from a can balancing on the frame).
The battery is brand new. I had some issues recently (read my "battery died" thread) so I guess I'm maybe being overly paranoid, it seems that "if it ain't broke, don't try to fix it" doesn't apply to the VFR charging system. I have cleaned up the connectors and fitted an extra earth onto the frame. I will have a look at the idle voltage but may need clarification on what to do with those results as I didn't fully understand what you were saying in that regard. I have noticed the headlights do brighten up from idle as you start revving but I think that's because as you said, the bike is not gonna charge at idle, and they don't get progressively brighter so that isn't really worrying me. Thanks for your help.

 

I just went through a harness rebuild on my 90.
This was one of the first things I tried and it didn't help
When I tore apart my harness I had a melted connector and a melted ground wire coming off of the R/C

Sounds like you have some bad connectors in the harness or a bad ground.

 

I just ordered the super mosfet kit from roadstercycle.com...I am installing it on my 2000 VFR as a preventive upgrade and the fact that I am paranoid because of all of the known issues. With this kit, you basically disconnect the power side from the old reg and tape it up and ty-wrap it somewhere safe. Mount the new RR and hook it up to the stator (cut off the old connector) and run the other wires (with fuse) direct to the battery. Seems very simple and takes the old wiring out of the equation. The other components still get power because all you have done was disconnect the connector from the old RR but the power leads are still connected to the battery.....