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Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:02 pm
by _Will_
So my bike has a good battery roughly a month old, it has gone from a full charge to needing another within a weeks time. After a charge fires right up when I'm leaving somewhere so it doesn't die riding around town. Do the experts believe this sounds like the infamous VR or more the considerably more expensive stator?

Electrical has never been my thing, growing up my role in the house was brakes, maintenance, and repairs without plugs (except alternators and spark plugs). Dad did electrical on the house and if it was auto electrical (we had no bikes) it went to the shop. What I'm saying is "type slowly" when discussing electrical. A shop isn't an option as my bike is my only transportation so I need to fix this on my day off and need to do it before I am stranded. Help is much appreciated

Re: Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:12 pm
by Dragon

Re: Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:27 pm
by _Will_
very helpful, one question though. Do you measure the voltage at the battery terminals? I have a multimeter

Re: Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:35 pm
by Dragon
_Will_ wrote:very helpful, one question though. Do you measure the voltage at the battery terminals? I have a multimeter

Yes, to find out if the VR is putting out enough voltage.... 13 - 14 volts @ 3000rpms..
the diagram states it all....

Re: Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:37 pm
by _Will_
Thank's a lot, I'll give it a shot tomorrow morning when the sound of a D&D at 3k won't make my neighbors hate me

Re: Alright Diagnosticians, help me out please

Posted: Tue Sep 08, 2009 11:40 pm
by Dragon
LOL

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 1:10 am
by mossy1200
_Will_ wrote:Thank's a lot, I'll give it a shot tomorrow morning when the sound of a D&D at 3k won't make my neighbors hate me
My neighbours like my bike unless the yoshi headers and custom muffler are singing the 10k tune.

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 8:51 am
by _Will_
as expected the battery is fine, no change in the voltage when running to 3k though. Will investigate further before work tomorrow.

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 9:21 am
by reelrazor
First, check the red wire FROM the VR for connectivity to the battery.

Check the big connector block coming off the stator for a good connection, and then check the white wires(input) at the VR for good connection. If either are green/corroded/fuzzy/look melted, clean that up.

Then you check the stator output at the white wires. You are looking for AC voltage. Check across each wire pair in turn (wire 'a' to wire 'b', then wire 'a' to wire 'c', then wire 'b' to wire 'c') You should be seeing +35 VAC at 3k rpms on each pairing.

If the stator output is good, your VR is bad.

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 9:42 am
by yamaha_george
reelrazor wrote:First, check the red wire FROM the VR for connectivity to the battery.

Check the big connector block coming off the stator for a good connection, and then check the white wires(input) at the VR for good connection. If either are green/corroded/fuzzy/look melted, clean that up.

Then you check the stator output at the white wires. You are looking for AC voltage. Check across each wire pair in turn (wire 'a' to wire 'b', then wire 'a' to wire 'c', then wire 'b' to wire 'c') You should be seeing +35 VAC at 3k rpms on each pairing.

If the stator output is good, your VR is bad.

You also have to check earth connections too for being clean & pristine.

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 10:28 am
by reelrazor
yamaha_george wrote:You also have to check earth connections too for being clean & pristine.
Yeah, that goes without saying-I should have though.

Grounds(earths) are not strictly necessary to diag a no/low charge situation. Grounds(earth) ARE a factor in overcharging issues.

And, are essential to long term health of the VR and should definately be addressed at time of VR replacement. It's a very good practice to extend the VR's ground wire so that it anchors at the main chassis ground buss(rear upper engine case bolt). It is resistance in that circuit (excess voltage 'dump' to ground circuit is made by passing excess to ground) that heats VRs up, and it is that heat that destroys the circuitry in the VR.

Re: Alright Diagnosticians, help me out please

Posted: Wed Sep 09, 2009 11:14 am
by _Will_
sounds good team, I'll do some wire checking tonight when I get home

Re: Alright Diagnosticians, help me out please

Posted: Thu Sep 10, 2009 9:23 am
by _Will_
hmmm, I'm trying to follow the wiring and look for bad connectors. Red wire at the stator is reading the same as the battery. Here's what I've found so far. I'm assuming dialectic grease is ok to use here?

Image

Image

Image

Re: Alright Diagnosticians, help me out please

Posted: Thu Sep 10, 2009 9:40 am
by _Will_
ok, so setting the multimeter to the ACV section I'm getting 49-50 on the meter between all the white wires @ 3k rpms. So if I'm reading this correctly that means the voltage regulator is bad according to the earlier posted chart? Correct?

Re: Alright Diagnosticians, help me out please

Posted: Thu Sep 10, 2009 10:09 am
by yamaha_george
_Will_ wrote:ok, so setting the multimeter to the ACV section I'm getting 49-50 on the meter between all the white wires @ 3k rpms. So if I'm reading this correctly that means the voltage regulator is bad according to the earlier posted chart? Correct?

Hi,
those three pics tell the story, MUCK all over the spades & sockets warped with heat.

Get rid of those overheated items and replace them with:

to QUOTE myself :-
Guys,
In another VR thread I did give the proper part numbers for the RS Components spade connectors with silicon rubber sheaths. Here they are again (& they are available thro the internet http://www.rs-components.com/index.html )

6.3mm spade terminals (male)....Pt/No. 488-1279
6.3mm recepticals (female)........ Pt/No. 488-1235
Receptical covers .........................Pt/No. 488-1314
spade covers................................Pt/No 488-1320

These are soft flexible covered terminals that can be silicon glue injected to really keep out water for dirt bikes (even power washers) or just use conductive {DIALECTRIC} grease in them or use as is which has been fine for everyday wear & tear in the UK.
UNQUOTE


Please do NOT use the sh*t plugs from autozone in hard blue plasic :swear or you will be on here giving us grief about odd electrical problems