Cleaning the exhaust pipes?

[Rusty]

That sounds good .... for tar .. those horrible boiled on spots and lumps that ruin everything I use White Spirit or Turps as my father used to call it .... just put some on a cloth / rag and rub the pipes and the tar will literally dissolve ... just keep going till it's all gone and finish off with large dollops of ACF50 spray  ;D ;D