honda CBF125 only outputting ~5V at regulator/rectifier

[bennet0989]

Basically my issue is what the title states, the wiring diagram for my bike claims the headlight and rear light should be receiving 12V but they are only receiving about 5V and i cant figure out why. I've traced the wires back to R/R and it doesnt getting any high anywhere. Indicators, brake lights all get 12V just not the headlight or brake light. Any thoughts?
Cheers
Alfie

[WD Forte]

I'd say it's either the stator coils or RR at fault.
Each one can be easily tested to determine which has failed.

post your diagram
____________________
bikers smell of wee

[bennet0989]

[stinkwheel]

Try with your meter on the AC voltage setting.

A lot of those small hondas have a split single phase charging system with direct lighting. Assuming you can only turn the headlight on when the engine is running, it is probably getting halfwave, positive earth AC to the lights.

Why are you checking, are the lights not working?
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[bennet0989]

Okay just checked stator, im getting about 98volts with the multimeter on the AC 200 setting and the bike at 3000 rpm, at idle its about 30ish
____________________
alfie

[bennet0989]

im checking because i tried installing LED tail lights, indicators and brake lights, and they don't work (only tail light) and they do work when they receive 12v straight out the battery. Its possible they wouldnt work in the system anyway but now i found my headlight and taillight were only getting 6v this whole time which was maybe why they were so dim ( the reason i got the LEDs)
____________________
alfie

[WD Forte]

Just looked at the diagram
and reckon Stinkwheels right
Those cheap bastard at Honda stuck 1970's lighting on a modern EFI bike

read that on DCV and it probably would look like 5v ish DC
and NOW we hear the OP's put LEDs on it!
____________________
bikers smell of wee

[stinkwheel]

It will mostly work with LEDs but you need positive earth or non polarity sensitive headlight bulbs. You need negative earth flashers.

You can't use an LED stop and tail light because the stop light part is negative earth and the tail light part is positive earth.

Source: The charging system on Mrs stinkwheels Honda Wave is exactly the same and I have LEDs on it.

Video showing the two different polarities in the same bulb holder:
https://youtu.be/Rb336rspMh8

I used these headlamps, they are good. Flicker very slightly at idle but steady when riding. Way brighter than the standard ones. Passed the MOT with them and it was put on the beam pattern tester.
https://www.classiccarleds.co.uk/products/compact-led-headlight-h4-p43t-472-motorcycle-hi-lo-beam-conversion-9-32v
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.