Noise at 4k RPM

lsdpoet

0
Joined
Aug 22, 2012
Messages
33
Location
Huntington Station, Long Island, NY
Bike
bike#61=2010NT700,silver
can't figure this out...bike runs fine...valves just checked...when in motion and tach hits 4000rpm the bike makes a noise similar to when we were kids and put playing cards in bicycle spokes...very annoying sound. When bike is in neutral I can rev it to the limit and no noise. Noise appears only when riding and tach hits 4000 exactly.
Anyone else experience similar problem? Any ideas as to why?
Thanks for any help.
 
Re: Puzzle

When it makes the noise pull the clutch in and tell us what happens.
Is the noise from the motor or driveline?
Right side or left?
Is the noise synced with rpm above 4K?
Drag a brake and see if the noise changes.
More clues please.
 
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Re: Puzzle

Might need to have the valves rechecked just to make sure the adjusters are tight. A lot of noises that come from engines can only be heard under load. Just a thought.
 
Re: Puzzle

junglejim said:
When it makes the noise pull the clutch in and tell us what happens.
Is the noise from the motor or driveline?
Right side or left?
Is the noise synced with rpm above 4K?
Drag a brake and see if the noise changes.
More clues please.
Click to expand...

As well as how many miles on the bike and what happens accelerating through 4000 and then decelerating through 4000 with trailing throttle.
 
Re: Puzzle

Nordakoda said:
Might need to have the valves rechecked just to make sure the adjusters are tight. A lot of noises that come from engines can only be heard under load. Just a thought.
Click to expand...

It is possible but not likely. I like Jim's suggestions.
 
Re: Puzzle

lsdpoet said:
can't figure this out...bike runs fine...valves just checked...when in motion and tach hits 4000rpm the bike makes a noise similar to when we were kids and put playing cards in bicycle spokes...very annoying sound. When bike is in neutral I can rev it to the limit and no noise. Noise appears only when riding and tach hits 4000 exactly.
Anyone else experience similar problem? Any ideas as to why?
Thanks for any help.
Click to expand...

Just so I am clear,
1. Did YOU do the valves? Did the noise appear right after the valve check?
2. If you accelerate hard is the noise period very brief as you pass through 4000 and then if you let off the gas, do you get the same noise as you decelerate through 4000?
 
Re: Puzzle

Few notes: bike has only 11000 miles...noise appears only when rolling on throttle and hitting 4000rpm...no noise when rolling off throttle, even above 4k....bike performs fine despite noise...dealer checked valves and they were in spec.
Thanks for all the input.
 
Re: Puzzle

The NT will make a "raspy" noise at ~4K on acceleration as it comes on the pipe. This noise is normal and is an induction drone thru the airbox. If you can find another NT I think you will find it makes this noise.

Hope this helps!

Mike
 
Re: Puzzle

mikesim said:
The NT will make a "raspy" noise at ~4K on acceleration as it comes on the pipe. This noise is normal and is an induction drone thru the airbox. If you can find another NT I think you will find it makes this noise.

Hope this helps!

Mike
Click to expand...

I believe that Mike is correct here.
Mine has always done that at 4000rpm.
There is also a similar but different noise at 2700 rpm.
Above about 4500 rpm the sound changes again.
I believe that it is a combination of induction, combustion, exhaust and mechanical noises that result in something that I used to worry about but now enjoy.
Don't worry too much about noises unless they change unexpectedly.
My drive-line is very noisy on over-run but has been doing it for nearly 80,ooo km.
There is never any metal in the oil and it runs brilliantly.
It almost certainly is NOT A PROBLEM.

My Suzuki is very quiet compared to the NT, but above 7ooo rpm is starts to howl (mostly induction roar).
It is a VERY pleasing sound.

Macka
 
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Wear ear plugs. They help a lot. Without them, my NT used to sound like it was a bucket of rocks because of the drive line noise. It's better now, but still loud. Ear plugs fix that. :)
 
Thanks for all the input, guys....took it to the dealer today and he and a mechanic took it for a ride...they both said it was induction noise and not a problem...so, I guess I'll do what a lot of you do and try earplugs...if that doesn't work I will reluctantly have a beautiful 2011 NT700 for sale...
Thanks again for the help.
 
lsdpoet said:
Thanks for all the input, guys....took it to the dealer today and he and a mechanic took it for a ride...they both said it was induction noise and not a problem...so, I guess I'll do what a lot of you do and try earplugs...if that doesn't work I will reluctantly have a beautiful 2011 NT700 for sale...
Thanks again for the help.
Click to expand...

Don't let a little induction noise scare you off, it is totally harmless and just the engine's way to tell you that it loves to breathe free. Most of us have grown to love the noise as it's the NT telling you that it is getting into its "feisty" rpm range where it develops maximum horsepower and torque.

Mike
 
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