Jump to content
Sign in to follow this  

Induction noise?

Recommended Posts

My bike mixes a whirring/whistling/harmonic type noise around 6k+ rpm.

 

It's loud enough to hear on the highway when I'm in 5th, but is the same relative loudness when I'm going slow.

It's not very high pitched or annoying. It seems to undulate/pulse slightly.

Is this induction noise or is my valvetrain about to go? 

 

Bike has about 15k miles.

Share this post


Link to post
Share on other sites

My bike mixes a whirring/whistling/harmonic type noise around 6k+ rpm.

It's loud enough to hear on the highway when I'm in 5th, but is the same relative loudness when I'm going slow.

It's not very high pitched or annoying. It seems to undulate/pulse slightly.

Is this induction noise or is my valvetrain about to go?

Bike has about 15k miles.

Have you checked in the intake ? You may have one of those vornados in there. .

Sent from my iPhone using Thumper Talk mobile app

Share this post


Link to post
Share on other sites

My bike mixes a whirring/whistling/harmonic type noise around 6k+ rpm.

 

It's loud enough to hear on the highway when I'm in 5th, but is the same relative loudness when I'm going slow.

It's not very high pitched or annoying. It seems to undulate/pulse slightly.

Is this induction noise or is my valvetrain about to go? 

 

Bike has about 15k miles.

FCR39 ?.....Ever since I installed FCR39 it makes a slight turbo-deisel noise.  :thinking:

Edited by billdirt1
  • Like 1

Share this post


Link to post
Share on other sites

do you have a mcct??

 

if i had mine too tight , it sounded like a supercharger on higher revs!

Share this post


Link to post
Share on other sites

My bike mixes a whirring/whistling/harmonic type noise around 6k+ rpm.

 

It's loud enough to hear on the highway when I'm in 5th, but is the same relative loudness when I'm going slow.

It's not very high pitched or annoying. It seems to undulate/pulse slightly.

Is this induction noise or is my valvetrain about to go? 

 

Bike has about 15k miles.

 

Is it a new noise or been apparent since any modification ?

Share this post


Link to post
Share on other sites

Is it a new noise or been apparent since any modification ?

Did a frame swap, had everything apart. Put it back together, noticed the sound.

Only things that really changed were some decently sized dents in the exhausts header, switched to 20w60 oil for the summer and Honda Coolant.

Share this post


Link to post
Share on other sites

FCR39 ?.....Ever since I installed FCR39 it makes a slight turbo-deisel noise.  :thinking:

mine does same since i put an fcr on, can really hear it with airbox door off, i kinda like it  :ride:

Edited by carlspeaky
  • Like 1

Share this post


Link to post
Share on other sites

Search Airbox resonance. Mine does it and it's common on these bikes.

Share this post


Link to post
Share on other sites

My FCRMX carb whistles at steady lower throttle positions. But not bad, I think it's pretty normal for a flat slide to do that. Mainly because it opens from the bottom to the top. Unlike your stock cv carb which twisted open and had air going through top and bottom. Think of it kinda like blowing over the top of a beer bottle or soda pop bottle, similar principle.

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...