Charging gremlins - HELP!

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

naughtyG

Well-Known Member
Joined
Jul 31, 2008
Messages
6,436
Reaction score
13
Location
Freo, Western Australia
So now I've replaced both my R/R and battery, and I'm still having problems. :damn angry::damn angry::damn angry:

Here's what I'm seeing:

- voltmeter across battery on idle shows 12.07 VDC
- revving the motor brings it up to a max of 12.30 VDC - not enough to charge

Measuring across all 3 wires from the stator, I am getting:

- 16-18VAC on idle
- when revving, it goes up to an indicated 125-130 VAC. Is this normal!? I was expecting a max of around 50 VAC :ummm:

If I unplug the red and black wires from the R/R, and measure its output there with the motor running (stator output plugged into R/R, of course), I get:

- around 4 VDC on idle
- as I rev up it goes down to just under 1 VDC :ummm::confused2::ummm:

Shouldn't this be showing around 12.9 VDC on idle, and up to about 14 VDC revving up? BTW, this is the same with both my old and new R/Rs.

What does this all mean? Does anyone think that my stator is shot? What's with the high AC voltage?

I just wanna ride - only 10 days left and I'm off traveling again.. :bang head:
 
Should be getting 13V or more at idle and up to 14 when RPMs increase . Also yes should get around 50VAC from stator when reving. If both R/Rs are showing the same I would check connections or for shorts. Pick up coil test? Also are you sure one or both R/R's are good?
 
I'm pretty sure the R/R are both ok. Or were, anyway.

The thing freaking me out is the AC output showing up to 130 V when revving - I thought it would go 50 V max. Anyone?

Also, when measuring the R/R output between the red and black wires, shouldn't that also show 13-14V?
 
I'm pretty sure the R/R are both ok. Or were, anyway.

The thing freaking me out is the AC output showing up to 130 V when revving - I thought it would go 50 V max. Anyone?

Also, when measuring the R/R output between the red and black wires, shouldn't that also show 13-14V?

DO NOT, REPEAT DO NOT measure voltage between red and black on your R/R. Quickest way to kill it. You are basically shorting it out. There is no load on it and it is WAY BAD.
The only time you can do is this is for a very very very short time to make sure you have the positive and negative terminals correct.

As for the 130v, make sure you are on VAC on your meter. As long as it is over 50v above 5k rpm and all three leads are equal you should be ok.'
Also make sure you are checking between the leads from the stator only. NOT the stator to ground, once again, between the leads on the stator.
According to our tech manual our R/R is capable of 200vdc. Page 8-16 under specifications.

Follow the trouble shooting guide Bro, it wont lead you wrong.
Hence why I posted it for you. :punk:

Cheers
 
Ya I've seen that troubleshooting guide b4, I need to go through this again methodically.

I'm pretty good with electrics, and it's freaking me out.

Defo measured the stator output between any 2 of the 3 leads. 16-18VAC at idle, and highest I've seen is 130 VAC at about 6-7k rpm. As long as that's normal it all good.

I've measured the resistance of the red wire from its plug (to the R/R) to the battery and it's just over 1 Ω.

Also measured the resistance from the black wire (its plug to the R/R) to the battery and it's less than 1 Ω, so those seem all good.

I cannot understand what's going on. 12.03 V on idle, rising to 12.7 V revving. WTF?

I also checked (remember I swapped harness last year) and ended up redoing the crimp fix - no change.

Feels almost like there's a short somewhere, or something draining the shit out of it. I dunno, everything's working A-OK other than it's not charging, and killing the battery after riding a while, especially in slow traffic when the fan's on a lot.

I just haven't got time for this. 10 days left in FL b4 I go traveling again, and I just wanna ride, not troubleshoot! On top of that my girlfriend's arriving 2moro, for the last 10 days here.

hmm..
 
Sounds like you are gonna have to choose between riding the bike or riding the girl friend :rofl_200:

Now on to the bike. Your red wire seems pretty high on the resistance.
If it is over 1ohm that is going to reduce the voltage to the battery by quite a bit.

V=IxR

Using the above formula to solve for current then using current to solve for voltage drop it might explain your lack of voltage at the battery.

Disconnect the red wire from the r/r and check the resistance on that wire alone. Mine reads .5 ohms. Probably lower but that is as low as my cheap little meter reads

Also it is connected straight to the battery???
That can give you .5-1v increase in charging capacity. Trust me :bang head:
 
Defo gonna ride the gf - it's been a month!!

Ok I'm gonna double-check that red wire too. It's not going straight to the battery - it's going the way Yamaha does it from new. Through crimp and starter solenoid, I believe?

My old R/R (newer style with fins) had a soldered wire on the black that ran straight to the battery. The replacement does not - it's connected to a bk/red stripe wire that goes to a bolt on the frame just above the - battery pole. Then there's a really short bk wire going from that bolt to the battery. I've checked those two wires and the frame connection and they all were ok.

I think I'm gonna just run both the red and black wires from the R/R straight to the battery, with soldered on wire extensions, and if that doesn't work, I'll be looking for R/R #3..

The weird thing is, originally I had a problem with the 3-pole block connector (from stator to R/R) melting. After replacing it, all was fine. Then it melted again (replacement block wasn't that heat friendly). At Central FL tech day, I trashed it and replaced with crimp-on connectors, and connected those straight into the R/R connector. Again all was fine - 13.5V charge to battery.
A couple of days later, no charge.
Before memorial day ride, swapped my R/R with Kyle's spare bike one. Again I'm good - 13+ V to battery. Half-way thru the ride, bike won't crank when hot. Got home measured - no charge. Swapped back to my R/R, still no charge.

Thought the battery was dead, as well as R/R, since stator output was great. Swapped battery, new '05 R/R from Pinwall Cycles, and here I am - no charge. Frustrating.
 
ok dude here is your simple answer. You have an intermittent short in your stator, probably arching to ground on the flywheel after it gets hot and under load sitting at a light with the brake light on signals on and fan running!!! Mine was doing the same thing drove me absolutly nuts. Replace the stator, backing plate and oil seal while your there. Here are the links I purchased from and received my parts the same week. Good luck and post your results....Thanks, Mike
http://cgi.ebay.com/NOS-YAMAHA-VMX1...rcycles_Parts_Accessories&hash=item2c5387c6de

http://cgi.ebay.com/NEW-YAMAHA-V-MA...rcycles_Parts_Accessories&hash=item563ccb742e
 
ok dude here is your simple answer. You have an intermittent short in your stator, probably arching to ground on the flywheel after it gets hot and under load sitting at a light with the brake light on signals on and fan running!!! Mine was doing the same thing drove me absolutly nuts. Replace the stator, backing plate and oil seal while your there. Here are the links I purchased from and received my parts the same week. Good luck and post your results....Thanks, Mike
http://cgi.ebay.com/NOS-YAMAHA-VMX1...rcycles_Parts_Accessories&hash=item2c5387c6de

http://cgi.ebay.com/NEW-YAMAHA-V-MA...rcycles_Parts_Accessories&hash=item563ccb742e

WOW if that's the answer I'll be your friend 4eva!!!! :worthy::clapping:

Oh and welcome here - I see this is your first post..
 
OK, I've taken the plunge - new stator purchased, and put in an offer on that back plate kit. We'll see what happens, fingers crossed!
 
Back
Top