If there are problems likely to beset all of us, they tend to be electrical. Ferret looks at some common specifics that teach wider lessons
You often hear folk banging on about certain electrical components endemically failing on certain bikes. Usually stators and regulator/ rectifiers. Let’s take the Suzuki GS/GSX range as an example; they’re all well known for it.
The universal oversight here is the fact that nearly all of the well-meant solutions offered are actually directed at the symptom, the failed component, and not at the actual problem, the reason for the component’s failure.
Simply replacing them without establishing and addressing why they have given up means you’ll soon be replacing the reg/rec and/or stator again.
The most likely cause of malfunctioning electrics is ‘bad earths’. The GS reg/rec has its earth lead fixed to its body via one of its mounting screws. The metal plate that it is fixed to, along with some other electrical giblets, is held on to the side of the battery box with a single M6 nut.
The battery box itself is rubber mounted.There is an earth lead coming from the loom which is fastened to a different screw on the electrics plate and there is another earth lead coming from the loom which is fixed to one of the battery box rubber mounts. The battery’s earth lead is fixed to one of the crankcase bolts. A convoluted route that worked OK when the bike was new, and would have lasted well enough in a kind climate (i.e. not here). Those of us who like to keep old bikes running have to be prepared to make necessary repairs and improvements.
On the GS, the accepted solution was to fit a Honda Superdream reg/rec. The reason it worked isn’t that the Honda unit is better, it’s that people generally connected its earth lead directly to the battery negative terminal, thus bypassing the reason for the failure of the original unit.
The Honda VFR and CBR ranges from the late 1980s onwards are equally notorious.
The connectors at the reg/rec, alternator and sometimes even the pink solenoid plug are all prone to melting. Lots of folk will tell you that these parts are simply not up to the job. The root cause is internal deterioration of the wiring loom. Not what anyone wants to hear.
Looms on modern bikes are not soldered together like they were back in the 1970s.
Owing to the frankly ludicrous complexity of 21st century motorcycle wiring systems it would be far too expensive to manufacture them in this way, and they would last far too long. Open one up and you’ll find a large number of joints si
