Not sure about Tom Tom 1? Depends on the supply voltage the unit needs. It may well be 5V, or some other voltage lower than The bike's electrical system. Does the cigarette lighter plug look like it contains a solid state transformer? If it does, then no you can't just chop it off. That would put 12V straight through to it cause trouble.

You need to have a look what it says on the cigarette lighter plug and check what the cradle's input voltage needs to be. Have you got a manual for it?

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