I need help with engine noise QUICK!!

[250Rocket]

Hi guys, long time no see ya. With the weather nice out forum posts have morphed into actually riding. Hope you guys (and girls) are enjoying too. Anyways, I have a little problem and I would need some quick help incase this is an issue, my warranty expires on the 16th. So i've searched and come up with nothing.

First, it's not.

Gas tank noise, vibration resonance noise (at 5.5k or 8.5k RPM), not low speed squeak, or any other major ones i've come across.

The Problem.

The engine gives off a weird whine/hissing noise and it comes from the heart of the bike.

Diagnosis

It's there at idle to redline (haven't tried but i figure) clutch in or out and it get's louder with higher RPMs.

It's quite noticable when letting off the gas and letting it coast down.

Very little hiss/whine when revving in neutral. It's not gear specific.

Stored it properly with Sta-bil without draining the carb but letting it run for 5 minutes after adding.


I only noticed it recently, not sure if it was there since restoring it. Gas has been changed 2 times (3/4 tank fills)

I mean any little noise it makes it bugs me to know what it is. If you tell me it's normal i wont have a problem but the bike is almost like my child and I would hate for it to be sick.

Thanks Guys

[250Rocket]

The only other thing i could add is i did an oil change before storing it with synthetic 15W-50. It's within the temperature specs of operation and it's at the correct level of fill.
And the performance level is still the same.

[Yoda]

Double check all your hoses? Might be a vacuum hiss from a cracked or loose hose.

[250Rocket]

Originally Posted by Yoda

Double check all your hoses? Might be a vacuum hiss from a cracked or loose hose.

Will do although it's not persay a hiss and it's not a whine. There's no word i can think of to describe it.

So the best idea i can give you is a mix of the two.

[BlueRaven]

Are you able to make a video with sound and post here so we could hear it and try to diagnose your problem?

[morrgun]

if its a sort of musical note type whine then you have the same problem as me its actually the vent on your tank mine actually got so loud today that i could hear it while sitting in traffic so i was looking online to see if anyone knew what it was and all the references to it are about the pressure valve for bleeding off fumes from the tank hope this helps as it has me as it was driving me crazy for the past while lol

P.S. i own a black 250r so i was sitting in traffic today in brilliant sunshine ;(

[250Rocket]

Originally Posted by morrgun

if its a sort of musical note type whine then you have the same problem as me its actually the vent on your tank mine actually got so loud today that i could hear it while sitting in traffic so i was looking online to see if anyone knew what it was and all the references to it are about the pressure valve for bleeding off fumes from the tank hope this helps as it has me as it was driving me crazy for the past while lol

P.S. i own a black 250r so i was sitting in traffic today in brilliant sunshine ;(

Did you even bother to read my first post in it's entirety

I thank you for your input but I clearly know it's not the tank. It has to do with the engine.

On a side note it's not as noticeable anymore. Could have just been something temporary or an environment effect.

I'll get back to you if it comes back or I figure out what is is. If anybody has any ideas it would help but no more rush.

[Ramen]

I have that hissing, too, but only notice it when around 40+ mph, and not all the time.. It's not a constant hiss. It's repetitive, like a steam engine train, but much quicker. Not loud, either.

Hasn't effected performance, though.

[draco413]

i get something simular to that but only when i am riding

[adri99an]

I do too---sounds like a hissing sound from under the gas tank area.....I think it's normal....doesn't affect performance......

[250Rocket]

Exactly guys. Thanks for the reassurance.

Like mentioned it doesn't effect performance or anything for that matter but i didn't know if it could lead to a problem later on and that's what caused my initial concern.

Big THANK YOU to all who helped.

[jonthechron]

Lets go riding together, then we can compare noises

Just got my 6A on Friday.

[250Rocket]

Originally Posted by jonthechron

Lets go riding together, then we can compare noises

Just got my 6A on Friday.

Congrats.

I'll have time come May to go riding. I'm in finals mode and the only time I take my bike out at the moment is when I use it to go to school.

[LazinCajun]

I hate to ask a stupid question, but could it just be the (can't think of the name) fan that turns on when your engine starts to get too hot?

[jonthechron]

talking about the radiator cooling fan

[250Rocket]

Originally Posted by LazinCajun

I hate to ask a stupid question, but could it just be the (can't think of the name) fan that turns on when your engine starts to get too hot?

I thought of that already, but again thanks for the input. The fan is very distinguishable when not moving fast and the noise is not it.

I'll post a video after exams right now i'm only checking forums on study breaks, don't have time to do much else.