what would piston slap sound like?

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the trail rider
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what would piston slap sound like?

Post by the trail rider »

just for reference guys i want to know just in case because i am going to ride my bike 1 or 2 more times before i go in and do the piston+ upgrades. just so I dont screw it up thanks.
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kdxquebec
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Post by kdxquebec »

piston slap=flaq que flacc quekek kaka flac clacc

Start the bike remove the seat and airbox cover then listen then put your ear in the air box and listen
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KDX220PHIL
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Post by KDX220PHIL »

Ahhh, that's what it sounds like :rolleyes: .
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KDXer
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Post by KDXer »

Come over my house usually late Saturday night when I arrive home after a night out on the turps. You will probably hear " Are you Pissed 'n' >SLAP< !!! :lol: :blink:
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RBD
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Re: what would piston slap sound like?

Post by RBD »

>|<>QBB<
the trail rider wrote:just for reference guys i want to know just in case because i am going to ride my bike 1 or 2 more times before i go in and do the piston+ upgrades. just so I dont screw it up thanks.
Piston slap is a rattle sound mostly when the bike is idling.... when you rev the engine (no load) the rattling will increase as the RPM increases.

Piston failure is just around the corner.
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canyncarvr
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Post by canyncarvr »

You know the noise the KDX makes all the time...especially when the clutch is not engaged (lever not pulled) and there is only 700ml of oil in it?

Well, it doesn't sound like that.

Kind of close, though. It's easy to say, harder to discern...but the clutch is certainly more related to some rotary goings on, and piston-slap noise is not.

Certainly see if pulling the clutch makes a difference in what you're hearing. If there is a difference, it's not piston-slap you're hearing.

That doesn't mean it's not happening though!! :wink:

If you're hearing it...it's in bad shape.

Consider the source
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the trail rider
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Post by the trail rider »

i haven't started or checked, i was just wondering what it did sound like just in case i did hear it i could stop the motor before it blew.
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Post by jafo »

I'm not totaly positive on bike pistons but on car pistons, if it's not to bad, there will be a dull knocking sound, usually will go away after the engine is warmed up. Now, I figure a piston is a piston so I would think it should do the same thing with a bike piston. The sound should diminish as the engine gets warmed up. It's caused by having to much piston to cylinder clearence. As the engine warms up, the clearence tightens up and the sound either goes away or diminishes. It all depends on how much clearence there is between the piston skirt and cylinder wall.

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Post by RBD »

jafo,

I kind of agree with you, but on two strokes it can be more of a clicking rattle and will change with load on the engine and RPM
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