More electrical testing....
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- bikemonkey
- NWAA Supporter
- Posts: 1524
- Joined: Tue Dec 27, 2011 12:33 pm
- Bike owned: 92 NC30, 90 VFR750
- Location: Oxfordshire
More electrical testing....
Bike over-heated and had a flat battery last night.
I'm suspecting the reg/rec for the flat battery.
I'm getting 55-60V at 5krpm from each stator winding to negative.
Still don't understand the resistance on my multimeter so I'll post a picture of what I have it set on, but I'm getting around 2.6-3.2. Bear in mind this is a GSXR alternator (don't know if it makes a difference but it might) plus the wiring I did between the alternator and the reg/rec was not the best and will be being re-done, so readings are probably off.
13.2 volts on the battery at idle and no change at 5krpm and no change to when the bike is off.
Fudged reg/rec?
I'm suspecting the reg/rec for the flat battery.
I'm getting 55-60V at 5krpm from each stator winding to negative.
Still don't understand the resistance on my multimeter so I'll post a picture of what I have it set on, but I'm getting around 2.6-3.2. Bear in mind this is a GSXR alternator (don't know if it makes a difference but it might) plus the wiring I did between the alternator and the reg/rec was not the best and will be being re-done, so readings are probably off.
13.2 volts on the battery at idle and no change at 5krpm and no change to when the bike is off.
Fudged reg/rec?
- CMSMJ1
- Moderators
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- Joined: Thu May 01, 2008 9:42 am
- Bike owned: NC30-No9
- Location: Chesterfield, United Kingdom
Re: More electrical testing....
I would say so.. Something not working with your new wiring maybe?
Earthed right? Can you trace the wiring to the reg rec plug and it does get the 50v AC?
Got to be something simple...it always is with electrics!
Earthed right? Can you trace the wiring to the reg rec plug and it does get the 50v AC?
Got to be something simple...it always is with electrics!
IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
- vfrman
- Senior Member
- Posts: 1390
- Joined: Sat Apr 05, 2008 7:54 pm
- Bike owned: NC30, 1098s
- Location: Layton, Utah, USA
Re: More electrical testing....
Run through this http://www.electrosport.com/media/pdf/f ... iagram.pdf and see what comes out the other side....


- bikemonkey
- NWAA Supporter
- Posts: 1524
- Joined: Tue Dec 27, 2011 12:33 pm
- Bike owned: 92 NC30, 90 VFR750
- Location: Oxfordshire
Re: More electrical testing....
All alternator readings were taken from the reg/rec plug.
So I got the 50AC from each winding, more actually, and I got 2.6-3.2 on this setting from each winding to the other.
I blame the high resistance on my shitty wiring.....

I ran through the sheet you stuck a link up for vfrman, cheers.
Got to the checking of the RR and got a solid one on what I think is the diode test function on my multimeter when putting the positive to positive of the RR and the negative to each winding input.
Edit: Then checking it the other way round with the negative multimeter lead on the positive of the RR and the negative on each winding input and got 0.5-0.56 on each.

Not sure if that's right, but if it is, it means a fudged reg/rec doesn't it?
So I got the 50AC from each winding, more actually, and I got 2.6-3.2 on this setting from each winding to the other.
I blame the high resistance on my shitty wiring.....

I ran through the sheet you stuck a link up for vfrman, cheers.
Got to the checking of the RR and got a solid one on what I think is the diode test function on my multimeter when putting the positive to positive of the RR and the negative to each winding input.
Edit: Then checking it the other way round with the negative multimeter lead on the positive of the RR and the negative on each winding input and got 0.5-0.56 on each.

Not sure if that's right, but if it is, it means a fudged reg/rec doesn't it?
- speedy231278
- NWAA Supporter
- Posts: 1549
- Joined: Tue Jul 03, 2012 11:58 am
- Bike owned: RVF400, TZR125, ZXR750R
Re: More electrical testing....
You'd have to ask a Gixxer person what the windings should measure. The stock NC30/35 windings are supposed to be 0.1-1.0 Ohm but there's no reason think the GSX-R ones would automatically be the same.
Still, if idle, off and revving to 5K produce the exact same voltage, I'd be tempted to say there's nothing getting back from the R/R to the battery, or it's eating everything the R/R can throw at it. 13.2V at 5K (presuming lights off, being a 30) is pretty weak. If you leave the bike running, does the voltage slowly drop?
Still, if idle, off and revving to 5K produce the exact same voltage, I'd be tempted to say there's nothing getting back from the R/R to the battery, or it's eating everything the R/R can throw at it. 13.2V at 5K (presuming lights off, being a 30) is pretty weak. If you leave the bike running, does the voltage slowly drop?

- vfrman
- Senior Member
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- Joined: Sat Apr 05, 2008 7:54 pm
- Bike owned: NC30, 1098s
- Location: Layton, Utah, USA
Re: More electrical testing....
So, what reading did you get with the first diode test?
- bikemonkey
- NWAA Supporter
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- Joined: Tue Dec 27, 2011 12:33 pm
- Bike owned: 92 NC30, 90 VFR750
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Re: More electrical testing....
Sorry that wasn't clear, the reading didn't change from the 1 you see in the picture.
And I haven't checked if the battery voltage was dropping at idle yet, will do later after I pop into work to cash in some shares
And I haven't checked if the battery voltage was dropping at idle yet, will do later after I pop into work to cash in some shares

- vfrman
- Senior Member
- Posts: 1390
- Joined: Sat Apr 05, 2008 7:54 pm
- Bike owned: NC30, 1098s
- Location: Layton, Utah, USA
Re: More electrical testing....
Well, if you are getting the 50 VAC and the 13.5 VDC isn't changing as you increase RPM I would have to agree that your reg/rec isn't letting the proper voltage go to the battery. Better that than too much and cooking it.
- bikemonkey
- NWAA Supporter
- Posts: 1524
- Joined: Tue Dec 27, 2011 12:33 pm
- Bike owned: 92 NC30, 90 VFR750
- Location: Oxfordshire
Re: More electrical testing....
Yeah I'm thinking that too, want to confirm it first.
I did another diode test with the negative multimeter lead on the negative of the reg/rec and the positive on each alternator input and again it didn't change from the one. But switch the two multimeter wires round and I get the same 0.5-0.56 reading as from using the multimeter on the positive reg/rec pin and the negative multimeter wire.
Anyway if it is really fudged what would be the best replacement?
I did another diode test with the negative multimeter lead on the negative of the reg/rec and the positive on each alternator input and again it didn't change from the one. But switch the two multimeter wires round and I get the same 0.5-0.56 reading as from using the multimeter on the positive reg/rec pin and the negative multimeter wire.
Anyway if it is really fudged what would be the best replacement?
-
- Moderators
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Re: More electrical testing....
I think you have a bad earth somewhere, you reg/reg is doing the job of converting the voltage.
I will assume with the ignition off the battery voltage is less than 13.5.
Run a new earth from the reg/rec to the battery direct and check the voltage.
This is turning into a bit of a xilvia though,
the bikes not running right, overheating (probably due to bad mixture) and now its dying.
I will assume with the ignition off the battery voltage is less than 13.5.
Run a new earth from the reg/rec to the battery direct and check the voltage.
This is turning into a bit of a xilvia though,
the bikes not running right, overheating (probably due to bad mixture) and now its dying.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...