battery de-charging, mosfet replacements, etc

Randy Grein rgrein at
Wed May 23 00:12:49 PDT 2012

Yes. No excuse for a wimpy rectifier. Easy enough to build one (6 diodes) but the combined rectifier/regulator makes your, or rather Ernest's recommendation better. 

Randy Grein
rgrein at

On May 22, 2012, at 4:08 PM, Dave & Tracy Thomas wrote:

> looking thru some emails in bike folder, have you tried this yet
> 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.
> Ernest Montague: author
> -----Original Message----- From: Jo Rhett
> Sent: Monday, May 21, 2012 3:23 AM
> To: Suzuki SV650 Mailing List
> Subject: battery de-charging, mosfet replacements, etc
> So I have finally got my garage set up at the new house where I can work on the bike.  I've still got the de-charge problem, which I have been working around for 3 months by recharging the battery nightly.  It just goes on the tender immediately when I get home.  But I took the bike to Santa Cruz yesterday and it died a few blocks from my house on the return trip, so the de-charging issue is clearly getting worse.
> I talked to the guy in fremont, but he has no idea when he'll have parts again.  Anyone know of other sources for rectifier replacements?
> Also, I thought someone recommended I double-check the coils but I can't find the e-mail saying how I should check those. Care to remind me?
> -- 
> Jo Rhett /  velociRaptor Racing
> #553 WERA 

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