Hay all

Trying to find out why my VFR 400 NC30 is slowly draining the battery. So far I've taken it to battery centre who say the battery is fine and taken to a auto electrician who said the charging on the bike is fine!

So the only thing left is that there could possibly be a connection problem causing it to slowly drain the battery. I got a friend of mine to bring his multi meter and we tested a few of the connections

We measured the voltage across the battery and got a readying of +/- 12.75 volts. Then we tested for leakage which should not be more than 1mA our reading was 0mA

We then started the bike (bike was cold) and again measure the voltage across the battery and found that it was charging perfectly at about 14volts. The only weird thing was that when we revved the bike to about 3000 - 4000 rpm the voltage dropped to about 13.7 volts. I didn't want to rev the bike any higher as is was still cold.

Is this normal for the voltage to drop because the little that I understand is that it should increase the voltage not drop it. If this is not right what could be the problem?

Sounds like classic reg rec failure -

I would try and see the charging output of the generator too...

Yep, the fact that the voltage is dropping sounds like the regulator isn't functioning correctly.

Thanks guys...going to take a volt meter to it tomorrow and check out the regulator.... and will report back my reading

SouL wrote:Thanks guys...going to take a volt meter to it tomorrow and check out the regulator.... and will report back my reading

Hey mate,
Let me know how you go. I think I've got the same problem. My battery went from fully charged to dead in 3 days. I only bought it about a week ago, but the seller told me he bought a new regulator/rectifier less than a month ago..

jonno92 wrote: I think I've got the same problem. My battery went from fully charged to dead in 3 days. I only bought it about a week ago, but the seller told me he bought a new regulator/rectifier less than a month ago..

Jonno, get a multimeter and do some simple checks. Odds are that you'll need a new battery and a new reg/rec.

There are some very crap reg/recs out there, just because it was new doesn't mean it will work!

What sort of checks should I do, Cammo, and how? (I'm a noob with electrics)

What sort of reg/rec should be used, and is there a specific brand which makes good ones? Are they bike specific or a universal thing?

Cheers

Specific to the bike.

However you can easily adapt an R6 reg/rec to fit.

Right so got home yesterday and with the aid of a multi meter checked out my rectifier.

These are the reading I got although apprently I missed out on a few which I need to do to double check but all seems to be fine

On the rectifier it has 3 x YELLOW, 1 x RED/WHITE and 1 x GREEN wires and these are the readings I got (hopefully I didnt miss any other measurements that I eneded to take )

Hope this may make sense to some: (reading taken in kilo Ohms)

YELLOW 1 + RED = 7.22
YELLOW 1 + GREEN = 7.30

YELLOW 2 + RED = 6.7
YELLOW 2 + GREEN = 6.82

YELLOW 3 + RED = 7.53
YELLOW 3 + GREEN = 7.07

use this guide to go through the charging process and it should highlight any issues as you go through it
http://www.electrexworld.co.uk/pdfs/Tro ... G-&-RR.pdf