Charging issue 1999 VFR 800 FI

minidazzler

hey lads,

So I'm having a little issue with my bike and looking for advice on likely causes if anyone is interested....

A few weeks ago I got on my bike at night and it just wouldn't start, I use it every day, but the clocks reset and it wouldn't even begin to turn over. I jumped it with great effort and got it home where the next morning it again wouldn't start.

I checked with a multimeter and the battery was at 11.6 volts, a little low but not extremely so. All fuses were good, and on sttempting a start voltage dropped to 2 volts.

checked the rectifier and while I didn't write down the values, it seemed to be in the right range at the time anyway.

Eventually jumped the bike again off the car and revved like crazy to try to force a charge, when the multimeter went to around 13.6 volts. It held the charge pretty well then.

Starting it was a bit of a balls, just taking longer than it should but it worked away grand seemingly because I purposefully have been riding at very high revs(. 6-7k)

Tonight I drove about 2 miles stopped for petrol and again battery flatted, luckily I jumped it really easy this time but I need to sort out this issue. Whatever it is....


So to shorten..


Battery dead on night.
Jumped it,
Stopped working again,
Jumped it and kept revs high to try to force a charge
Seemingly works as I've been driving away for 2 weeks.
Short low rev trip killed the battery but still jumped.

given the facts before ye can anyone take an educated guess at the problem. I've come up with either the Rectifier being the problem due to me taking mostly short trips in the city with slow moving traffic and it overheating

The battery just being bollixed because it's not quite new

Or maybe the alternator but I think that's the outside shot.

I don't have the cash to work through all possible things so looking for a decent educated guess for the first stop on the road to recovery.

Thanks for reading.

Gavin.

blade1

Check for a burnt wire.
Without seeing the bike it's hard to pin point but start with the cheapest fix first.

CJhaughey

Most likely reg/rec on these Honda's. Its a weak point on an otherwise reliable machine.
Battery could also be buggered as its been badly charged for a while.
Check the earth from the battery as well, and clean the contact if necessary.
Open the connector from the alternator to the reg/rec and check for oxidised contacts/ melted connector and clean and use some dielectric or silicone grease on them as yo remake the connection.
Check the plugs as they enter the reg/rec unit and make sure they are all clean and not corroded.
Any corrosion or dull contacts in the supply side from the alternator to the reg rec will lead to charge issues and possibly melted or damaged connectors.

Richard tea

As the lads said. Also my recent charging problem was the connection under the shrink wrap positive going to the battery was loose.

My original charging problem was the reg/rec. Once I wnt over 6000 rpm the battery stopped charging. Considering most of my commute is over the 6000 rpm range my battery would be near dead upon arrival.

If it turns out to be you Reg/Rec I can recommend a mosfet type as a good fix.

galwaytt

Add above, assuming no connection issues it's probably the regulator/rectifier.

Btw 11.6 is too low ...needs 12.3 minimum

jimgoose

A healthy automotive battery will show 12.6v at full charge. Charging voltage is usually around 14.3v. 11.6v is way too low and it's possible that the battery is damaged because of the charging situation. To confirm what the lads said, it is quite likely that the crappy Honda reg/rec has given up.

RAIMEIS

Hello
I have a bike too. Suddenly after 4years of goodness loyalty it was dead as a dodo. Without warning. Impossible to charge again.

If I may recommend:

Buy a lithium-ion Battery

1 It should last 8 to 12 years (so they say)
2 the weight is a third or even less than a lead battery (quite important on a motorbike).
3 I left me bike for 7 months in my basement car park. It was covered with dust and I did not unplug the negative side.
It started like a charm at first attempt.

The price is double than a normal battery and it is well worth it.

Stiletto72

I had the same issue with my old 800fi. It was the R/R.
Replaced battery and R/R, problem solved.

Oryx

When its Honda and charging issues its usually the RR. Ive seen so many need replacing I know the part codes by heart

minidazzler

Got my new battery and r/r working away grand now. It was a hit I really could have done without but it's cheaper than paying for taxis

landmarkjohn

minidazzler wrote: »

Got my new battery and r/r working away grand now. It was a hit I really could have done without but it's cheaper than paying for taxis

I have the same problem with my VFR800Fi....... plus....every now and then riding along and the red Fi light comes on and engine goes dead then comes back sometimes straightaway but last night was a few seconds and so I switched off my lights and she came back before I came to a dead stop.

Sometimes after it has been running and stopped I turn on ignition and hit start, nothing, off on ignition again and she starts.... I really must try and fix this... OP, how much did you pay for the parts? Thanks.

CJhaughey

When you replace the parts make sure all the earths and connections are clean and good.