Worrying noise at high RPM

Mary-Ann Horley · Posted: Tue Sep 17, 2002 9:04 am Post subject: Worrying noise at high RPM

I have a very worrying noise coming from my engine above 11500 rpm. It does'nt seem to effect performance from the engine as much as from the driver. I checked the oil level, tightened and sealed the exhaust, checked the power valve and had a good look around. Help i can't work it out and i'm thinking this is gonna go Bang soon

Bruce Woodrow · Posted: Tue Sep 17, 2002 9:15 am Post subject: Worrying noise at high RPM

What kind of noise is it? Rattle, Knock, whine, etc.?

Mary-Ann Horley · Posted: Tue Sep 17, 2002 12:43 pm Post subject: Worrying noise at high RPM

It sounds like an intense rattle or grinding noise that starts at 11500 rpm and stops immediatly as soon as i take my foot off the accelerator.

Bill Wright · Posted: Tue Sep 17, 2002 4:25 pm Post subject: Worrying noise at high RPM

Maryann,

That sounds like gear box. Remove the side cover and see if the reduction gear(s) are damaged.

Bill Wright
"Get on Course!" with FK www.formulakart.com

Nick Weil · Posted: Tue Sep 17, 2002 5:38 pm Post subject: Worrying noise at high RPM

Also check to make sure your pipe is not too close to anything. The occasional bump from behind can cause the pipe to touch. It only becomes audible after the RPM's really get up there...

Nick Weil
SpeedQuest Rotax Website

Mikko Nassi · Posted: Fri Sep 20, 2002 5:09 am Post subject: Worrying noise at high RPM

As nick said, check to see that the exhaust wasn't loose. I've driven a rotax with the exhaust tapping the brake disk and there's a noise that starts at just about 11000RPM, you don't notice it at the lower rpm's.

quote:
Originally posted by Nick Weil:
Also check to make sure your pipe is not too close to anything. The occasional bump from behind can cause the pipe to touch. It only becomes audible after the RPM's really get up there...
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