charging system nfg ; battery takes charge but dies after riding

Ernest Montague afm199 at
Sun Feb 12 11:05:33 PST 2012

Charge your battery. Let it sit a half hour. Check  the voltage. If it is close to 13 volts it's good. If is 12.4 or less, it is shit.

Now, with a good charged battery in the bike, start it and rev to 4000 rpm. It should read above 14 volts at the battery. It probably won't if you have the stock SV regulator.

If it reads 13.4 or so, you have a problem. If it reads lower as you rev higher it is probably the regulator.

Before you change anything, unplug the three wire plug from the alternator and check pin to pin voltage AC.  It should be around 65-70 volts a to b, b to c , and c to a. If it is, then your regulator is probably bad.

I actually had a bike in a couple weeks ago that had a rotor  magnet let go but that is scarce.

So, under 14 volts DC at the battery, and 60-70 at the alternator? Replace regulator. Don't put in stock gen one, use a GSXR or CBR 1000.

On Feb 12, 2012, at 10:52 AM, Jo Rhett wrote:

> So I replaced the battery in my street bike about 5 months ago.  It's died on me three times in the last 2 weeks.  After doing some careful testing it's clear what's happening -- I can put it on a battery tender and get 4-5 (errand/trip) rides from it, but the battery is dead after that.  But it does accept a charge and does run quite well.
> I think that the charging system is screwed, rather than the battery being already dead. Am I wrong? What should I replace?
> -- 
> Jo Rhett /  velociRaptor Racing
> #553 WERA

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