R65LS Electronic tachometer issues - any advice ?

[inveloveritas]

Hi all

I’m still struggling with this tacho. I’ve tested the multi plug at 6, 8 and 5 and I’ve no volts at any of them and no ground.

I’ve pulled the tank and pulled all the multi plugs under there, red, black and the white one (I think the white one has the green and blue hot wire that feeds number 6) and they all cleaned up nicely.

I then pulled the green and blues that feed off the coil and cleaned all that up.

Still nothing at all. No volts on hot, no ground, Jack.

What do I do next Any other joints anywhere that might be problematic Like the tacho is getting some power as it is moving fractionally when it’s running, but clearly not what it’s needing to work properly. I am certain that the problem is in the wiring, everything that I’ve had issues with electrically has come down to rubbish connections somewhere.

Just to help everyone’s recall it’s an ‘84 R65 LS.

[Bob_Roller]

I'd go to the ignition coil, one terminal should have two green/blue wires, the other terminal should have two black wires.
One of those black wires goes to the connector on the tachometer.
Theat's the power wire
I'd check the solderless connector at the coil for security of wires, corrosion, etc .
All of the circuits in the tachometer share a common ground, it's the solid brown wire on the connector .
According to the wiring diagram, the black wire does not go through any connectors, joints it's one piece of wire .
I'd do a continuity test from the coil end, to the pin on the connector that has the black wire .
After 38 years and who knows how many owners, anything is possible !!!!!!

[georgesgiralt]

Hello,
On my 1982 R65, the wiring was original and untouched (I know, I bought her new in 1984)... But I had problems, mainly charging and poor lighting.
One day I decided to buy a new harness. Not cheap but it solved all my problems at once and everything is running fine now.
I compared the old and new wiring. The old one had corrosion running all the length of the wires and that caused a lot of resistance. And it was very very stiff...
So IMHO, do not spend hours and hours trying to fix a dead horse. Buy a new harness and spend the time riding. ......
Just my 2¢ ™