its most likely not internal then. i was thinking it was related into the top end of the motor ----- Original Message ----- From: "Andrew" <aos+yahoo@xxxx> To: <dmcnews@xxxxxxxxxxxxxxx> Sent: Monday, April 22, 2002 12:08 AM Subject: Re: [DML] Clackety clackety clackety? > On Sun, 21 Apr 2002, Patrick Cowan wrote: > > > did the noise change pitch with idle advancement? > > The noise definitely changed pitch, but did not sound directly > proportional to engine speed.