We receive many calls from people looking for a replacement CB antenna for their Harley Classic or Honda GoldWing motorcycles. If you are simply wanting to unscrew the existing factory antenna and replace it with a Firestik antenna, then you will need an adapter.
Many of the Honda GoldWing bikes like the GL1500 and GL1800 are using an 8mm (0.315") thread at the base of the CB antenna. Firestik manufactures a quick disconnect adapter (model K-1A8M) for the GoldWing's that allows the use of Firestik antennas or any antenna with the industry standard 3/8"-24 thread. Firestik does not manufacture an adapter for the Harley (6mm thread), however, we are aware that a 6mm - 3/8-24 adapter is available. Because of the small diameter (0.236"), we do not recommend that heavy-duty Firestiks be used with the 6mm adapter. .
Sierra Electronics: www.sierra-mc.com of Troy, Ohio, USA (1-800-338-6938) sells adapters and fold-down joints that work for both the Harley and Honda bikes. Sierra Electronics also supports and sells some of our Firestik products. It is likely that they will be able to help you with a complete system that features Firestik brand antennas and accessories.