Fried electrics

[pinkwaferwalrus]

Electrics not my strong point but have taken care to put the elctrcals all back as original after rebuild. Lights, turn signals, horn and brake all worked ok, but no neutral light and when I turn the kill switch to run it fried the live feed from the battery to the fuse (but didn’t blow it - melted the wire though. I have worked out that if I isolate the regulator it doesn’t seems ok, but no neutral still - although I haven’t got her running yet.
I guess the regulator is knackered but odd that it has gone when off the bike, or have I done something wrong?

[summer0123]

You don't mention what bike you have but one thing is certain that you have a dead short on the system.
If the short occurred when you closed the kill switch ( ignition on) then the problem will be in the kill switch or on the cable back to the coils and regulator. If the fuse did not blow then you need to check the fuse rating and replace it with the correct rated fuse.
The other problem you will have is if you have passed a lot of amps into the system via the cable to the ignition switch and then into the kill switch and beyond then those cables will also most certainly be damaged and will need to be replaced.
A reliable bike must have a sound electrical system so you need to check the whole system right through.
Before you do anything else get the correct rated fuse in the system
The fault on the neutral light would seem not to be related to your dead short.
Good luck
paul

[pinkwaferwalrus]

Thanks Paul. Sorry, it’s a GT550m, and the fuse is 20 Amps and is which is correct according to the manual. I would expect it to blow given the current it must have been drawing but no. I even tried a 15amp and that didn’t blow either but still got too hot to touch.
I have checked the kill switch and it’s fine, so I am thinking it’s either something wrong with the regulator or, like you say, the connection to the alternator. Will keep looking. Cheers.

[summer0123]

If you are melting ( or seriously heating) the cable to the fuse holder and the correct rated fuse is not blowing then make sure that cable is not damaged and touching the frame.

[pinkwaferwalrus]

Problem solved. Comm connection to alternator missed off isolation washer so both terminals going to earth. All ok now but still unsure why fuse didn’t blow. Only damaged wire at fuse so have replaced and all looks good now. Cheers for help and advice.

[summer0123]

Glad you solved the problem. I agree it is strange the fuse did not protect the system.
It can only be that the current never went higher than the fuse rating which is why there is no cable damage.
paul

[barney01]

I would deffo change that fuse just in case there is a problem with it !

[Alan H]

Problem solved. Comm connection to alternator missed off isolation washer so both terminals going to earth. All ok now but still unsure why fuse didn’t blow. Only damaged wire at fuse so have replaced and all looks good now. Cheers for help and advice.

Not sure what you mean by comm connector to the alternator. Do you mean the green wire that goes to the rotor? This comes from the regulator via the orange/white from the kill switch and should be fused, but does go through a current limiting resistor in the regulator. It will let sufficient current pass to heat the wire, and not blow the fuse if the battery isn't fully charged I suppose.
If you mean the red from the rectifier (to battery) that should also be fused. All these connections go through plugs and sockets so 'shouldn't' be wrongly connected.
Check the two connectors behind the left panel that go to rectifier and alternator haven't been swapped over - colours should pass through the plug/connector connections.
(Black) neutral wire is from the neutral bulb and earths at the neutral switch and doesn't go through multiplugs, just a separate wire. Split it near the neutral switch area and earth the feed side from the bulb (not the switch side) - the neutral light should come on if the bulb's OK and ignition on.

For info, the kill switch puts power to the coils as well as the regulator on the orange/white wire via the 6 way multi connector (Black, Black/white, White and 3 x orange wires) near the coils and the other (Green, Orange/White Black/white and 'blank') near the reg.