Headlight stopped working, nothing obvious will fix it.

[mkjackary]

Driving at 7pm today on the a12 when the main and fullbeam goes out. Pull over, do some diagnostics, sidelight is on the same fuse circuit as the main beam and it still works. Every other light and horn still works besides the full beam, main beam, and fullbeam dash indicator light.

Changed the fuses, nothing new, got my mum to drive up with a new bulb, nothing, tried two different new bulbs and nothing. Checked for obvious cables being unplugged or anything, maybe the wind blew one loose, but narp. What else could it be? I'm going to take off the tank and check every cable I can, try and get a multimeter to check if there is power going to the plug or whatever, anything else I should try?

Cheers

[mkjackary]

Also worth noting about 15 seconds before the light went out
I downshift to overtake, gearbox does something funny (all this could be irrelevant, but I have no idea) and instead of going from 6th to 5th, I assume it went to a much lower gear as to keep up I had to rev the shit out of it, almost like when you accidentally go into neutral, but the neutral light never went on.

I went back up, only one click to top gear, then it was fine. The ride back was fine (followed my mum's car for the 30 odd minute drive)

Don't know if this helps at all or maybe it is a slightly dodgey gear box and bad timing.

I thought maybe that caused a surge of power through the alternator and blew a fuse, but narp, fuses are fine and dandy

[Nobby the Bastard]

try bypassing the earth on the bulb connector.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[mkjackary]

[Nobby the Bastard]

[Hong Kong Phooey]

^
I think misunderstandings are in evidence here.

In other words, if the earth is already broken, but it's common to both main and dipped beam, then how can it be faulty?

Multimeter is your friend, multimeter is good mmmkay.
____________________
'81 CG125, '97 FZS600 : '99 CBR600F4, '09 KTM RC8

[mkjackary]

Apologies, long day, been outside in the cold for about 3 and a half hours trying to fix it and waiting for a ride so brain isn't firing on all cylinders.

I have bought a multimeter that should arrive tommorow, and hopefully I can get it fixed for my 7pm-3am shift on Saturday.

[Nobby the Bastard]

[WD Forte]

https://www.cycleterminal.com/wpimages/Honda-CB750F77-Wiring-Diagram.jpg
____________________
bikers smell of wee

[mkjackary]

Before I got the bike the previous owner got a new set of handlebars and didn't drill through the hole to keep them in place, so they moved a lot, my solution was a couple of layers of tape to give the area a bit more girth and then it stayed noice and tight. Recently it has been commingling loose, particularly on the right.

I'm thinking, and hoping, that when I got that wierd false neutral, and I had to pin the throttle for a second or two so as not to get rear ended, I possibly twisted the whole mechanism, pulling out a wire in the controls. Once it is a decent hour I will give that a go, if I can do this without having to drain the fuel tank and fiddle about with a horrible wiring loom then all the better.

If that doesn't work I'll try shoving the flux capacitor onto the shiny bit of the thing and into the hole that hurts the least when you lick it.

[Pete.]

Take the switch clusters off and fix them properly. When you're in there look to see if the tape you have put round the bars has bunched up and messed with the wires or switch.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[doggone]

Test your replacement bulb before going to deep into this

[mkjackary]

So, multimeter is here. Took hand control off, no loose cables or anything obvious, so my Eureka moment didn't amount to anything, I tried taking it apart further after this photo was taken but it just doesn't want to, I would have to take the switches off from underneath and I don't think the issue is here. https://i.imgpile.com/i/vdc9o.jpg


Took the headlight off and took the bulb out, the bulb is fine, as I said before I have tried an old bulb that I know works and a brand new bulb in this one's place, so I know it isn't the bulb. Tested continuity of the socket, the left and right ones are connected, so they must be the positive for the low and high beams, meaning the top is earth. But wierdly I tested the continuity of the earth and the shiny bit of the forks, and nothong, but there is continuity between the shiny bit of the forks and the two live cables, which isn't good obviously.

Is there any useful info anyone can gather from this? It just confused me more.
https://i6.imgpile.com/i/vdiaj.jpg

[Nobby the Bastard]

[Copycat73]

[Nobby the Bastard]

[bamt]

The way you are holding that socket, ground should be the right hand side connection, low beam on the top and high beam on the left.

Put the meter onto volts, turn on the bike so the lights should be on, and measure between the top pin and the ground pin. If you've got 12V there then either you have two duff bulbs or there is a mechanical problem with the pins connecting to the bulb.

If not, put your black lead to ground (try a good, unpainted part of the bike - maybe the bolt holding your horn in, or the engine) and red lead to the top connection. You should get 12v there. If not (and you are sure you are using the meter correctly and the ground connection to the meter was good) then your problem is somewhere on the +ve side wiring. If you do, then the problem is an issue with the ground wire.

[Copycat73]

[mkjackary]

[mkjackary]

[Nobby the Bastard]

[bamt]

[Hawkeye1250FA]

[iooi]

[Pete.]