Yes, you back probe the connector.

problem found... my reg/rec is giving off 0.2v while the engine is running on all three yellow wires..wich means the reg/rec is fooocked...atleast a cheapy Chinese version is on its way...itl have to do till i get my pay from work to get a heavy duty one.

I still don't know why you didn't just not get a chinese one and get a CBR125 or R6 one for not much more... like everyone suggested...

i thought those needed modifications to fit? im not wiling to do any more modifications in the mean time.. i just wanna ride the bike before it starts to snow...ive had this bike for months...and not ridden it properly at all...im sure you know how im feeling....i just want to RIDE :D....i will buy an r6 one and fit it on during the winter when the bike is off the road...

xivlia, something I forgot to mention when testing for <2 volts between the three yellow wires with the engine running, multimeter should be set to ac volts.

xivlia wrote:problem found... my reg/rec is giving off 0.2v while the engine is running on all three yellow wires..wich means the reg/rec is fooocked...atleast a cheapy Chinese version is on its way...itl have to do till i get my pay from work to get a heavy duty one.

No it isn't, your not doing it right. The regulator is connected to the battery, so the voltage reading you get there should be the same as the battery is getting, ie 12 - 14v. Something isn't connected or set right.

Argh this thread has gone on for far too long.

Your making a mountain out of a mole hill, testing the electrical system is a doddle.

Follow this instructions and reply back the exacty replys. (fill in the blanks)

Firstly set you multimeter to resistance, if it has a scale pick 200, the smallest one.

Step 1

Disconnect the plug with 3 yellow wires that connects to the reg/rec loom.

Call one wire A, one B and one C.

Put a probe on the following

A and B: __________
B and C: __________
A and C: ___________

Step 2

With the plug still disconnected set the multimeter to AC volts, 200 (lowest setting) should be fine.

Make sure battery is fully charged and start the engine (have the lights off) at 5000rpm

A and B: __________
B and C: __________
A and C: ___________

Turn the engine off and reconnect the plug.

Step 3

Providing your regulator is wired up properly you can measure the voltage it is giving out at the battery.

Put the multimeter to DC volts, 20 will do.

Connect the -ve to the battery -ve and the +ve to the battery positive.

Measure the battery voltage with the engine turned off ______________________
Measure the battery voltage with the engine idling__________________________
Measure the battery voltage with the engine at 5000rpm _____________________

Measure the battery voltage with the engine idling and lights on _________________
Measure the battery voltage with the engine at 5000rpm and lights on ____________


It really is that simple.

The reasony your blowing fuses is your shortcircuiting, (connecting + and - together) the red and green wires your probably shorted with the probes.

Follow the steps above EXACTLY, with a pen and paper, then hit reply and fill in all the blanks.

To clarify the yellow wire test with the engine running, I said if you get continuous <2 VAC between the yellow wires then the regulator part of the rect/reg is stuffed. xivlia did this test and claimed to get 0v therefore he concluded a stuffed rect/reg.

You will not get battery voltage between the yellow wires only a voltage that varies anywhere from about 2 VAC to 13-14 VAC as the regulator chops the alternator output on and off to keep the average battery voltage within the 13-14 VDC range.

magg wrote:To clarify the yellow wire test with the engine running, I said if you get continuous <2 VAC between the yellow wires then the regulator part of the rect/reg is stuffed. xivlia did this test and claimed to get 0v therefore he concluded a stuffed rect/reg.

You will not get battery voltage between the yellow wires only a voltage that varies anywhere from about 2 VAC to 13-14 VAC as the regulator chops the alternator output on and off to keep the average battery voltage within the 13-14 VDC range.

You can't test the generator with it still connected to the reg/rec. This is why the Haynes and the Honda service manual state to disconnect it from the reg/reg.

Follow my insutrctions and test it on it's own, then plug it into the reg/rec and see what voltage you are getting at the battery.

If you are getting 50v into the regulator but nothing out then it is most likely the reg/rec is broken.

The reg/rec also does not 'chop' the generator on and off, this would be a MOSFET type device, the regulator / rectifier fitted to the VFR is a linear shunt design, is simply grounds out part of the unused voltage to maintain a stable 14v, this is why it gets hot, any excess voltage is burnt off, not 'turned off'. (Which is also why MOSFET types run cooler)

no i am getting the right voltage..im getting 12.70v at the reg/reg, but thats when im connecting the multimeter probes to the red/white and green terminals so thats fine.... however i tried to check the voltage between any 2 yellow wires while the reg/rec is connected and engine running....i was getting 0-0.2v...but thats because i never set my multimeter to AC, it was on DC instead....im gonna be trying it again in about 2 hours with the multimeter set to AC and gonna check what voltage i am getting at the yellow wires, while the reg/rec is connected and the engine is running..i can report back when im done.....i have already checked the 3 phases from the alternator and im getting 45-50v at 5k rpm...so thats fine. if i get < 2 VAC continuesly as magg mentioned, then the reg/rec is broken...

however i will try all the steps you told me to do Neo, and i will report back..i will do them tomorrow as its very dark at the moment here.

okay.. so i checked the three yellow wires at the reg/rec while its connected and the engine is running...at 2.5k rpm im getting 22-24VAC...i mean the AC volts is going in.. its just not getting regulated by the reg/rec.....what do you guys think? i know magg said <2 VAC would mean a dead reg/rec..but im getting 22-24v at 2.5k rpm..is that too much?