vf500 wont start... help plzz

Hello fellow vfr enthusiasts,

i was riding the PCH with my friend the other day, and we decided to take a break, after a 5 minute rest i tried to start up my bike again and it there was no power, no lights, no blinkers, no start, nothing it was completely dead.

I looked around the bike and realized that i had been riding the bike with the fuel in the OFF position (im not sure if this is relevant but I alos have a small petcock leak)

Upon bump starting the bike, it started up however It would not go over 30 mph and thats on 6th gear, and the bike sounded like it had asthma. It was struggling to go but I had to make it home somehow.
I got home and put the battery on a battery tender and apparently it had over 80% charge.

I have an 86 Vf500f in pretty good condition, and havent had any major issues, i got it checked out recently and everything checked out fine.

any suggestions on what the problem could be? If its a quick fix id like to do it, however before taking it to a mechanic id like to get some idea so i dont get ripped off.

thanks,

 

With the loss of power as described I would check the connector at the starter relay but bump starting it would not have cured that so I am at a loss.

 

Based on a very similar experience I had, sounds like you have an electrical short. When it happened to me, I chased ALL of my electrical wiring looking for anything abnormal. I found quite a few things that weren't right (a loose wire / several bare wires / a hot-side relay that was unshielded). I fixed everything I found, and that fixed my issue. Hope this helps.

 

Could be your starter relay connection is bad and not enough power is getting to the fuel pump under load. Was it 80% Cold start amps or was it 80% of 12V? A quick why to check if the fuel pump is bad on these bikes is to run a line from the tank to the carbs making it a gravity feed system, if the bike runs normally for a quick spin then you'll know what to check for.

Check the fuses as well. When I picked up the 500 I'm working on now the starter relay was shot and I had to jump it to turn over the bike. you can get the updated relay with an ATO fuse on Ebay for under $40.00 new. you just have to trim off the plastic locking tab on the plug so it fits in the new relay. Grab a set of pliers or a screw driver and jump the 2 terminals if the bike turns over then your relay is shot.

 

I had a similar problem today (see thread on 5th gen LED), I ran battery down because I was drawing more than the alternator put out. 80% is 9.6 volts, not nearly enough. Check all your connections for corrosion, you can pass 12 volts, but not enough current to keep charging. If battery dies again while riding (I miss the PCH), then follow Mellow Dudes link about how to diagnose electrical problems.

Search for "Stator" and follow Mello Dudes thread, excellent.

Found it:

http://vfrworld.com/forums/showthre...on-regulator-Stator-failures?highlight=stator

 

From what the OP said, he had "no power, no lights, no blinkers, no start, no nothing......". This would rule out the starter, and the battery because of his charge check once he was home. I believe this to be an ignition circuit or lighting circuit issue.

If it were me, I would remove the headlight assembly and surrounding fairings in that area, and look for the problem there. My money says that the problem is an old wire / connector / relay somewhere within the triple-tree area.

 

The four pin connector at the starter relay is kinda the heart of the power circuit and is well known issue with almost all of the interceptor/vfr products.

 

Aside from actual battery voltage it is the first thing to look at.

 

And that's where your VFR experience comes in. I am only speaking from general motorcycle wiring experience, as I am new to the VFR world.

 

Actually, 80% of a 12V battery is somewhere around 12.6-12.9V (depending on battery design - Could be a bit more). A 12V battery is technically dead @ 12V flat. Residual absorption will provide output below 12V, but that doesn't mean it's good for the battery. A good rule of thumb is - If you ever see 10.5V and you didn't just put a good load on the battery, throw it out and get a new one!

The OP said the words "battery tender", and I'm gonna guess that the OP said "80%" because that's the point where battery tenders go into final charge (flashing green light) and slow the charge rate to provide top-charge absorption.

That being said, his battery was mostly charged and not being drawn down by a constant drain. It sounds like a switched-on draw to me. My two cents.

 

All batteries consist of 6 cells that produce 2.1 volts each, a fully charged battery should be 12.6 volts. Anything less than 11.5 volts (plus or minus) is consider "dead". If some device says 80% charge, that to me says 80% which is 0.80 x 12.6 = 10.08 volts, but does 80% charge really mean 80% voltage? I don't know what the maker of that device meant. Having spent most of life in electronics (my father and brother were engineers) I do know that a highly resistive connection (corrosion) can indicate 12 volt on a meter, even light the lights, but not crank an engine.
I had a VW Cabriolet that the battery died, I went to Sears and bought a DieHard, which they installed. Three days later it died too. I went back to Sears and the smart ass said nothing wrong with the battery, you need a new alternator. I went back home and took apart the connection to the alternator and found the lug was sandwiched between two corroded washers. I sanded and cleaned all the parts and it worked fine from that point on. The connection could not pass the current necessary to charge the battery, alternator was fine. Battery terminals do it all the time.

 

Any time you're way down on power, check first to see if all cylinders are firing.

 

Thank you all for your suggestions, to clarify about the charge percent, i mentioned 80% because that is what it said on the battery tender instructions since the green light was flashing.

to update: within less than an hour on the tender the green light stayed lit and I unhooked it. I tried starting the bike again and still nothing, there is absolutely no electricity. (normally when I would put the key in the on position, my headlight would turn on, the gauges would light up, and the blinkers would work) this time I was getting nothing.

I will check my fuses next, and try again and if it still doesnt work I will have to take it to a mechanic since I am not very knowlegable or experienced in electrical, or advanced troubleshooting issues on motorcycles.

I will post more updates soon. thanks vfrworld

 

Hi thanks for your reply, Im not sure if it was exactly 80% because it was off the battery tender approximations, but after keeping it on for less than an hour it indicated full charge.. I tried restarting the bike with the charged battery and still no power or electricity.
What I dont understand is how after bump starting the bike, it sounded like it was chocking and not getting any throttle response, I was barely able to go up to 30 mph in 6th gear, and even after riding like that if it happened to turn off it wouldnt be able to start again.

 

I am going to check the fuses first and hope its only that, checking all that wiring sounds like quite the task

 

SoCalCeptor. PM sent.

 

i would guess it's bad contacts in the ignition switch. Get a voltmeter and trace the +12 from the battery to the switch, then check the voltage at the switch poles when the key is turned to the various positions.

 

Hi SoCalceptor - The quick look would be to check the ground circuit on your battery. It that isn't clean, you won't have much juice. Squirt a blast of contact cleaner or even WD40 into the key hole of your main ignition switch. If that isn't clean, you will get no juice anywhere, too. When you get it running, put a volt meter on your battery and see how much current is going through the battery. That way you'll know if the regulator/rectifier is running. Next, would be to check the alternator output, but I would do the ground and main ignition switch first.
Cheers,
Bill

 

The electrical contacts of the ignition switch are mechanically separated from the key tumbler slot=> spraying into the key hole won't clean any contacts...

 

"mechanically separated from the key tumbler slot" They aren't separated enough to not get cleaned up by a pressurized shot of WD40 or contact cleaner. That move saved my 1988 Yamaha Radian once upon a time.
Cheers