I’m not sure if this replacement electrical system smoke is compatible with old British bikes too….

“Here is presented for your perusal one Lucas Replacement Wiring Harness Smoke kit, P/N 530433, along with the very rare Churchill Tool 18G548BS adapter tube and metering valve. These kits were supplied surreptitiously to Lucas factory technicians as a trouble-shooting and repair aid for the rectification of chronic electrical problems on a plethora of British cars. The smoke is metered, through the fuse box, into the circuit which has released it’s original smoke until the leak is located and repaired. The affected circuit is then rectified and the replacement smoke re-introduced. An advantage over the cheap repro smoke kits currently available is the exceptionally rare Churchill metering valve and fuse box adapter. It enables the intrepid and highly skilled British Car Technician to meter the precise amount of genuine Lucas smoke required by the circuit.”