Earth cables - where should I have them? K100 LT '89

None were fitted when I got it as a stripped down project.

The only earth cable on my bike goes from the battery to the frame earth under the tank where the loom earths.

Should there be a cable from battery to engine? Gearbox? Should the ECU casing be earthed?

Currently have an issue with the cooling fan and temp warning light coming on when bike is cold.

Thanks

On my 93 75, I did the following modification as far as earth cables go:- I disconnected the under tank earth wire cluster- about 5 wires. Then bolted a bar with 6 threaded holes onto the frame where the 5 earth wires were connected. Then ran a cable from the bar to the neg.side if battery and connected the 5 earth wires to the bar. Also ran another cable from battery to one of the retaining bolts for the starter motor. Also made sure earth cable connection on transmission is clean and tight. Sorry for long winded reply but this has solved some earth/ground problems. Cheers Tom

+1 that...

Thanks, I've now fitted an earth to gearbox, and will do one to starter. Already got one to under tank point.

You'll sometimes see a small lead running from one of the master cylinder cap screws down to the frame. My TT didn't and earthed through the throttle cable ruining the throttle cable at the same time.

The ECU casing does not need to be earthed and I believe it should not be earthed.