The condenser serves two purposes, one to act as a reservoir of power to feed back to the primary side of the ignition coil, when then the points are open. At the same time absorb some of the coil output to stop the points arcing across, burning them out more quickly than would otherwise be expected. Renewing the condenser is highly recommended when renewing the ignition points. To check out the other ignition consumables and parts why not browse the online catalogue and 'parts list' fiche for your classic CB Four?
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