if you don't have a check engine light on its probably gonna be a bad speedometer head,there is no gear or cable on these cars that go bad.you need to check the wire harness that runs along the back/underside of intake manifold sometimes the wires will rub through on intake bracket and cause weird problems like this.there is only three things that could cause this speedo issue 1 broken wires to speed sensor(that usually makes chk.light come on)2 bad speed sensor(that also makes chk.light come on)3 bad speedometer. im gonna guess its the speedometer itself. honda tech 11yrs.