Battery Drains whiile sitting

My 1986 VFR750F has had an issue for a little while, the battery drains while it is turned off.

I looked into the factory manual and tried the linkage test




I failed the test and had about 10V on the meter.

So I started the bike and checked the charging voltage. It was 12.2V at 5kRPM

I shut the bike down and unplugged the 4 pin connector on the RR.



After unplugging this connector I rechecked leakage and it passed the test at 0V

I am guessing I need a new RR can anyone else confirm?

 

How long a period of time of sitting are we talking about here? It sounds like something on the 12V rail is making a connection to ground to drain the battery. I would test at certain points on the wiring harness at the fuse box to see if you get voltage while the ignition is turned off.

How old of a battery is this?

 

Battery is 1.5 years old and it is an agm. It has done this with two batteries. It was slow and as long as I rode every month I was fine now it is dead in a couple days.

I agree the 12 volt rail is the issue that is why I did the test in the manual and started pulling connectors until the short went away.

 

Reverse current leakage points to a failed diode in the r/r, so look for a replacement unit.

You got bit, he got bit, she got bit, they got bit, we will all have been bitten by the r/r !:chaingun:

 

Do you have a multimeter to test at different points in the harness and fusebox for voltage? That is what I would do first with the ignition off.
Seeing voltage at a certain point in the circuit where you should not in the electrical schematic with the ignition off is where I would start.
Begin at the battery itself and work your way down the chain.

 

Yeah, failed dioide in the bridge would not allow the battery to recharge when running, battery would just drain but how would this account for drain while it was sitting?

 

Yes I have a multi meter. I used it when I tested for a batter charge leak as suggested in the honda manual.

 

So if I get a new regulator I want a ricks right?

RICKS VOLTAGE REGULATOR RECTIFIER HONDA VFR750 86 RICK'S | eBay

 

Should work.

 

Huh also my battery drains like hell, but i use my bike almost everyday. I have the same problem as midias. When i start the engine the power on my battery was 11.97V, so i tryed it at 5kRPM and than it was 12.2 V. I hope its RR and not the stator (generator), beucase i bought a new one 2 months ago.

I will report the solution when i will find it.

 

R/R failure season :hss: glad I got the 6th gen.

 

Oh i forgot to wrote that mine is 6th gen

 

Run the R/R test with a diode checker and ohmeter and make sure you do not have a cell or two that went bad.

 

Just thought I would let you guys know. I had a bad RR and a bad battery. I don't know if one caused the other. The battery lost charge sitting on the ground and even with a fresh battery the RR would not go over 12.3V. New battery and regulator 14.3V at 5k rpm and the battery does not drain.

 

My regulator was just fine, but my stator died again... after 3000km. Now i have a new one and also installed a "Voltage indicator" (12v Battery Charge Warning Light, voltage indicator | eBay)

 

A bad R/R can cause a battery to go bad if the regulator lets the voltage run too high.

 

setting the battery directly on the ground is bad too not sure why just what I was taught many many years ago... glad you figured it out.... there is a cross over from a cbr RR that fits right up to the vfr..I have one but TOECUTER got it for me and it costs 1/3 what the vfr one costs...plus as TOE put it..."they grow on trees"

 

Do tell about this Crusty, do you have a Honda number or CBR model year we can pluck these R/R's from?

I think the problem with batteries on the ground is if you place them on concrete or asphalt- if you place them on something like a wooden board or a rubber sheet- that should help with ion leakage.
Placing them on battery tenders helps with storage too.