Usually I can avoid the last minute panic. This is a time when I do not think and reason like I should. Lately my battery is getting low and it will not start the engine. I got all upset and was going to do some serious electrical diagnosis. Triumph electrical parts are very expensive and I was worried. Then I realized the loud racing pipes are on the bike and I keep the rpm low so I do not make noise and get people mad. I was not spinning the engine fast enough to keep the battery charged.
Decades ago, I suffered through a few electrical engineering classes. We built an intricate circuit in the lab and it took us civil engineering guys a week of afternoons to get it to work. The entire mess of wires, resistors, and other goodies generated different electrical currents and impulses at various output nodes. The professor OK'ed the circuit and then he said "put this little resistor in the circuit near the ground." We did, and all of the circuit outputs were wrong. The prof said something like "That simulates a bad ground. Always make sure that everything is grounded OK. Check the grounds first when things do not work." He had us hook up the meters to the output terminals and then he moved a cord or wire around the circuit. The cord carried electricity from an independent source and it did not touch the circuit. The outputs changed. Something was happening. I am not sure what it was. Since then, I always read the instructions very carefully for electronic stuff and I actually do everything they say. Some of the minor things like grounding, component location on the vehicle, and cable routing seem to be pointless and optional, but they are very important. There are a lot of instructions with this air / fuel mixture gage and I follow them.
The components share a common ground on the engine block. Bike engines vibrate and the little wires from the components can fatigue and break at the junction where they connect to the ground lug. I use a gold plated ground lug and some dielectric grease between the lug, bolt, and block. This helps to minimize corrosion and the electrical resistance that it creates. A short piece of copper mesh cable is installed between the little wires and the lug. This cable flexes when the engine vibrates and it does not fatigue and break as quickly as a direct connection between the lug and the little wires.
Some of these materials are hard to find. A dab of anti-flux on each side of the wire mesh keeps the solder from being absorbed throughout the entire cable. The anti flux I use is from Allied Manufacturing in Bozeman, Montana
www.alliedmfg.co A good electronics solder is a big help. The stuff I use is in the picture. The mesh cable is Radio Shack desoldering cable. Most of these goods are stocked in a model train and airplane shop.