Project Veronica Part 3: Electrical Gremlins

Hey Guys, Matt here! Welcome to Part 3 of Project Veronica, thanks for sticking with me so far! In this update, I'll be taking my first foray into any sort electrical I'm a little worried to say the least. But with a bit of commonsense and some wiring diagrams, I'm hoping to sort out some of the electrical issues plaguing the bike.

So, let's get stuck in...when I got the bike back with the new Mikuni's, she was running a treat, except for the fact that at random intervals she wouldn't start back up. Weird. What got me was how she would start up just fine from a completely cold start...but after running for some 20 mins it wouldn't start back up no matter how hard I kick-started it.

After a series of asking friends, referring to the workshop manual and some serious forum-hopping, I figured it's got to be a couple of things:

  • Stator (alternator)
  • Battery itself
  • Battery charging system (Voltage Regulator/Rectifier)
  • Really dodgy cabling
  • Or all of the!

So I began to look at the under-seat wiring situation and boy...was it a bit of a Hornet's nest! 40+ year old wiring can be pretty messy, not to mention it had been hacked up a little which didn't help. So I managed to identify the stator and purchased a replacement through Mike's XS and bought a new battery from a local shop.

I was now in a position to do some testing so I began, I managed to kick the bike over and it idled well, after some testing with the multi meter I could see the battery voltage was hovering around the 10-11v range.Definitely on the low side I thought. A quick consultation with the service manual confirmed what I thought...idle voltage should be in the 14.5v range...give or take.

Glad I bought the rectifier then hey! But alas, it wasn't that easy...the under seat wiring harness had a mix of spade and bullet connectors so while it should've been a swap-and-go affair, it certainly wasn't now.

I visited the local Jaycar and managed to find a similar 6-pin spade-type plug that I could use which pretty much matched the existing plug on the regulator. So after some very careful massaging, I was able to remove the spade connectors and seat them in their new home, with a clip-fastened plug! Way more reliable than crusty old spade connectors.

At this stage I thought it would be wise to replace the worn-out battery with the new one and place the old one on trickle-charge juuuust in case. I should also check whether to install an isolation switch when the bike isn't running as I suspect there's a voltage drain even when the bike isn't running.

 After checking and double-checking connections, it was time to start 'er up and thankfully she started on the first kick. Checking with the multi meter revealed that the battery was sitting at a solid 14.5v at idle, which was right on the money. I let it run for about 7-10 minutes and then shut the bike down. Now the interesting took a good 10-12 kicks to get her to start again which is pretty next guess would be the ignition coils....or a clogged fuel tank vent!

The mystery continues...stay tuned!


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