what is the "whoosh" after shut off

[Jersey450R]

i know people know about this but i'm unsure. sometime after i shut my quad off, about 1-3 seconds later, a "whoosh" or a "whomp" comes out of my exhaust. i've heard it on more yamahas than hondas but i always wondered what it was. chad, you will probably know.

[chad502ex]

i'm unsure of the sound your trying to decribe... whoosh or whomp...:confused:

...it may be ignition of unburned gasses in the header/exhaust where the engine is spitting out fuel (rich) and the heat of the heater ignites unburned fuel. check for excessive black exhaust deposits on the exhaust tip.

without hearing the 'whoosh' or 'whomp' i can only take a guess.....;)

[Pappy]

That would be the sound of your azzhole de-puckering:devil:

[chad502ex]

Originally posted by Pappy
That would be the sound of your azzhole de-puckering:devil:

lmfao!!:D

[killroy]

i know what ur talking about....its sounds really weird

[chris46250r]

Originally posted by Pappy
That would be the sound of your azzhole de-puckering:devil:

I just spit Coke on my damn keyboard.

[chris46250r]

Originally posted by chad502ex
i'm unsure of the sound your trying to decribe... whoosh or whomp...:confused:

...it may be ignition of unburned gasses in the header/exhaust where the engine is spitting out fuel (rich) and the heat of the heater ignites unburned fuel. check for excessive black exhaust deposits on the exhaust tip.

without hearing the 'whoosh' or 'whomp' i can only take a guess.....;)

You know, its the sound that people joke about how a queers fart would sound. No friction, nothing but net, didn't touch the sides all the way out!:D

[Jersey450R]

Originally posted by chad502ex

...it may be ignition of unburned gasses in the header/exhaust where the engine is spitting out fuel (rich) and the heat of the heater ignites unburned fuel. check for excessive black exhaust deposits on the exhaust tip.


i'm pretty sure thats what it is, i've other guys ask before about it.

quote:
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Originally posted by Pappy
That would be the sound of your azzhole de-puckering
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pappy, thats just a given, i dont even hear it anymore, lol! :D

[the Z Man]

They other night I was changing my cam cnain and it did the same thing, what it was, the engine was just off TDC and moved into its resting state or TDC from the compression of the engine.

[Jersey450R]

idk...bike is definitly not running rich.

[d3ktrix]

My friends YFZ does it a lot, I always figured it was some un-burnt gas going off in the header/silencer. So I agree with chad.

[pro-rider46]

well when that t 25 turbo is spooling off idle it will continue to spool after shut down. so it is pushing out the exhaust,

[450rJam]

thats funny, mine has done it before also and I was going to ask what it was but always forgot about it by the time I got home

its like it came up on compression but didnt fire then the exhaust valve opened up and let it out