Probably a reg-rec problem

[wambam87]

Hi guys this is just to confirm my fears really.

Over the past 2 months the bike has slowly been loosing charge and needing charging up. Last week it started to loose a full charge overnight.

So today i charged the battery in isolation fully till the charger switched to trikle.
Put it back in the bike all is well. Went on a test flught got 20 miles away and she cut out. Then a nasty fuse popping smell came from under the fairing.

Open up fuse box and ive popped 2 fuses , but more alarming-ly ive cooked the battery completly , it looks like its going to explode seems split etc ( have removed it from the bike ) . I have read up and it appears that a faulty regulator rectifer is probalby the culprit.

Any other ideas? or am i along the right lines. I just hope that the fuses saved the other delicate componenets.

Cheers Sam.

Ps my Vfr is a 1992 import if that helps.

[petrolhead19]

If the battery has expanded then it sounds like your reg/rec was over charging it, i would get a new battery and reg/rec then test the voltage across the battery.
Hopefully you caught it in time before it cooked your cdi

[wambam87]

I thought that too , is there anyway of finding if the cdi is damaged or will i need to wait till i get new battery and reg-rec?

[lutorm]

If you've blown a bunch of fuses, it seems there must be something more wrong than just an overcharge. The voltage would have to go up quite a lot before the fuses would start popping just because of overvoltage, so make sure you don't have a short somewhere before you plug the new battery in. The fact that it would lose charge also seems to indicate there's something pulling a current when it shouldn't (though it could just be that your battery was fried, I guess).

[speedy231278]

I'd agree with the above. It doesn't sound like just a normal charging issue. Ruined battery yes, fuses other than the main occasionally blowing aren't usually caused by a dodgy reg/rec. You need to inspect the wiring on the two circuits that blew fuses to make sure there's not some damage somewhere that is causing shorts. After that, run the usual charging system checks with the new battery and reg/rec. If nothing is amiss, then personally I'd very quickly swap back to the old reg/reg just to confirm it was over charging, but obviously you want to do this VERY quickly to avoid doing any damage to the new battery. The old battery going flat very quickly could be a drain caused by a short, or it could be that the battery was knackered by the reg/rec and is unable to hold charge any more. You won't know until everything is sorted.

[wambam87]

Sorry I didn't make the fuses clear, after it cut out, I replaced the main fuse then bump started the bike. And it ran for 2minuets then it blew again. So it's more likely the rectifier. Hope that clears things up.