What is "piston slap", and what can silence it?

bamorris2 · #1 10-13-2009, 11:35 PM

I have what I think is piston slap, according to the symptoms that I've read online... Basically, only when the motor is cold, I get a clanking sound coming from the engine, will usually happen at low/mid RPM when under light load. After riding for about 5 minutes, the noise completely goes away.

So my question is, what exactly is piston slap, and can anything simple be done to hide the noise (besides pipes, earplugs, etc)?

From what I've read, it's not really harmful, but more of an annoyance.

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propane_peddler · #2 10-13-2009, 11:40 PM

Piston slap is too much clearance between the piston and cylinder wall. The reason its worse when cold is because the piston expands as it warms up. The only fix is bore the cylinders and replace the pistons to get the correct clearance.

Yachtman · #3 10-13-2009, 11:53 PM

I think the best solution would be to take back to the dealer for warranty

bamorris2 · #4 10-13-2009, 11:55 PM

Ok, so no quick and easy way to mask the problem (although I know that's not a popular choice)?

krwould · #5 10-14-2009, 12:03 AM

If this is your 2009 I would certainly take it in... could be something with the fuel injection, timing, ecm... anything can happen but might not be piston slap.

bamorris2 · #6 10-14-2009, 12:14 AM

Quote:

Originally Posted by krwould

If this is your 2009 I would certainly take it in... could be something with the fuel injection, timing, ecm... anything can happen but might not be piston slap.

Done that, and they confirmed it's piston slap, and is not warrantable, as it does not cause damage... Just seeing if there's anyway to quite it down a little. It only lasts for 5 minutes in the morning, but still...

krwould · #7 10-14-2009, 12:18 AM

Quote:

Originally Posted by bamorris2

Done that, and they confirmed it's piston slap, and is not warrantable, as it does not cause damage... Just seeing if there's anyway to quite it down a little. It only lasts for 5 minutes in the morning, but still...

No way I know other than a boring out and oversized pistons. I think that was mentioned before.

bamorris2 · #8 10-14-2009, 12:25 AM

Ok, thanks... I was just thinking that maybe some oil is better at masking sounds, or something along those lines....

I suppose I could always use a mini-torch through the spark plug holes to heat up the pistons every morning. LoL

krwould · #9 10-14-2009, 12:28 AM

Quote:

Originally Posted by bamorris2

Ok, thanks... I was just thinking that maybe some oil is better at masking sounds, or something along those lines....

I suppose I could always use a mini-torch through the spark plug holes to heat up the pistons every morning. LoL

Hehe! Nope none that I know of.. even if you would squirt a few shots of oil in the cylinders before you fire it up it would only last 20 seconds maybe!

No... no flames around the fuel pleeeease!!!

krwould · #10 10-14-2009, 12:37 AM

Really don't even think about an open flame in a cylinder, if an intake valve is open you may be in serious trouble if you know what I mean... so I hope you were joking!?