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Knocking (piston slap?).. new noise..

Posted: Thu Aug 15, 2013 6:01 pm
by DAQ421
So.. Today on the freeway I was moving along at about 80 in 6th.. I opened the throttle to pass a car and heard a metallic chatter. It sounds a lot like engine knock, but it's a lot more chattery..

Does not happen at low speed, no matter the rpm's..

Thoughts?

Re: Knocking (piston slap?).. new noise..

Posted: Thu Aug 15, 2013 7:15 pm
by DAQ421
DAQ421 wrote:So.. Today on the freeway I was moving along at about 80 in 6th.. I opened the throttle to pass a car and heard a metallic chatter. It sounds a lot like engine knock, but it's a lot more chattery..

Does not happen at low speed, no matter the rpm's..

Thoughts?

I think I'll reset the Motronic tomorrow, perhaps changing the exhaust has messed up the Fuel / Air mix..

Re: Knocking (piston slap?).. new noise..

Posted: Thu Aug 15, 2013 9:10 pm
by towerworker
What year is your bike and the miles? I'm thinking possibly the cam chain tensioner. Could you tell what side it was coming from?

I once had a very severe knock that suddenly appeared and thankfully suddenly disappeared. Turned out to probably be a small piece of carbon that broke away from the head of the piston and banged around till it blew out thru the exhaust.

Re: Knocking (piston slap?).. new noise..

Posted: Thu Aug 15, 2013 9:32 pm
by DAQ421
towerworker wrote:What year is your bike and the miles? I'm thinking possibly the cam chain tensioner. Could you tell what side it was coming from?

I once had a very severe knock that suddenly appeared and thankfully suddenly disappeared. Turned out to probably be a small piece of carbon that broke away from the head of the piston and banged around till it blew out thru the exhaust.
Hi..

It's an 04' with 24000 on the clock.

-Peter

Re: Knocking (piston slap?).. new noise..

Posted: Fri Aug 16, 2013 7:04 pm
by towerworker
If the sound is on the left side I'd think it's the cam chain tensioner.

Re: Knocking (piston slap?).. new noise..

Posted: Fri Aug 16, 2013 7:43 pm
by bransan
DAQ421 wrote:
towerworker wrote:What year is your bike and the miles? I'm thinking possibly the cam chain tensioner. Could you tell what side it was coming from?

I once had a very severe knock that suddenly appeared and thankfully suddenly disappeared. Turned out to probably be a small piece of carbon that broke away from the head of the piston and banged around till it blew out thru the exhaust.
Hi..

It's an 04' with 24000 on the clock.

-Peter
I have the 04' R1150R with 60k mi on the clock. I have never heard that noise at those kinds of speeds. I have run 100mph for long periods in Montana and never heard anything but the wind. I only run the best gas,ie.91 octane or better, and I only use Castrol GTX 20-50 oil. The chain tensioner,( as previously mentioned ),has never caused any issue for Me except at start-up, I'll get a little slap, slap sound but then it goes away after a few seconds.

By the by, it's time for the spline shaft lube!

Make sure Your running the best gas and the correct weight oil.

Re: Knocking (piston slap?).. new noise..

Posted: Sat Aug 17, 2013 8:57 am
by Buckster
Could it have been pinging from pre-detonation? I still get it sometimes when rolling on the throttle too hard to pass at freeway speeds.

Re: Knocking (piston slap?).. new noise..

Posted: Sat Aug 17, 2013 10:49 am
by DAQ421
Buckster wrote:Could it have been pinging from pre-detonation? I still get it sometimes when rolling on the throttle too hard to pass at freeway speeds.
This is what I was thinking.. (after I posted this).. It sounds like my old Chevelle when the timing was off..

I thought the Motronic was supposed to keep the timing and mixture in line?

-Peter

Re: Knocking (piston slap?).. new noise..

Posted: Sat Aug 17, 2013 7:14 pm
by towerworker
Mine will ping if I run poor quality fuel. Also it will ping severely if your fuel is poor and the motor is a tad over-heated. Stop and go city traffic is hell on an air cooled motor.

Re: Knocking (piston slap?).. new noise..

Posted: Wed Aug 21, 2013 9:18 am
by DAQ421
I ran a dose of Seafoam through the fuel system, and reset the Motronic, and the noise is gone..

weird..


-Peter