Melted connection? 450t

[Guest]

My bike lost all power while I was riding and smelled like burning wires. I noticed the positive connection to the battery was broken...I replaced that and started the bike again. It's started fine, but had very little power. I was able to limp it the last mile home.
while inspecting the wiring, i found this burnt connection in the headlight...

Anyone have any insight as to what connection this is and what it's going to?
or what might have caused it to melt?

 

[Brendan W]

Can you identify the original colours of the wires at the centre of the melt?
AFAIK that bike has the stator loop to the switchgear as standard wiring W/R and W/G.
What way is your generator wired, all three phases direct to the regulator?

 

[Gorminrider]

I noticed the positive connection to the battery was broken...I replaced that and started the bike again. It's started fine, but had very little power. I was able to limp it the last mile home.

That is very bad for the bike. They really don't like that. You might as well start and repair the burned bit. Get a wiring diagram and be sure everything is connect properly in the headlight bucket and elsewhere.

As to what other damage might have been done, check your fuse, be sure your battery is in good shape and go from there to see what works and what doesn't....cross your fingers-you might get away with it or you might not.

 

[Rich82GS750TZ]

And don't forget to refill the harness smoke after you get the wiring cleaned up.

 

[Grimly]

And don't forget to refill the harness smoke after you get the wiring cleaned up.

Need the Neg Pol stuff, which is increasingly rare. Lucas only brought out the Pos Pol because of classic car owners whinging.

 

[Guest]

So, I cut out the connection and soldered new wires in. Problem solved.
Next problem, it was only running only one cylinder. Turns out the ignition coil was burned up. I got a new set of coils and wires, and replaced both. Started up, sounded good. Took it for a ride and had almost no power. The same ignition coil was melted? Any idea what would cause this? I know bad wires could, but I replaced them too.

 

[Nessism]

Try starting the bike on one cylinder, and reving it up to 5000rpm while checking battery voltage. If the voltage spikes up higher than 15 VDC, then your R/R has failed, or it is not grounded, and when that happens there is high voltage though the system which often takes out the ignitor.

 

[Guest]

I tested the battery voltage when the bike is off, it's 13V, when it's on at an idle, it's 17.5V.
I also took off the r/r and tested continuity, which seemed to be fine.
also tested the voltage supply to the ignition coils. The working one was about 6-7, the one that has blown twice was about 14

 

[bonanzadave]

when it's on at an idle, it's 17.5V.

Thats not good. I believe Ed has your answer....
If the voltage spikes up higher than 15 VDC, then your R/R has failed.
The wire connections in your headlight had corrosion which creates a high resistance and then a lot of heat. Clean all the electrical connectors and connections with a spray cleaner like deoxit. Electrical contact cleaner. Run a dedicated ground wire from your Reg/Rect to the - post on the battery. Run a search for a replacement R/R.

 

[Nessism]

You are destroying parts because the charging voltage is crazy high. Make sure the R/R is properly grounded, the 450 has a really bad ground in that regard, and then test again. Shut down immediately if the voltage is above 15 volts and fix the problem(s).