Engine noise when idle

[Sjohan]

Hi I'm Johan and I'm new on this forum

This is my engine sound http://youtu.be/3LbKL4ZIC5M

On the film I take the clutch in and out no difference.
Pv is already adjusted and checked.
Is this a normal sound? Sound a bit to high for me. When I rev the engine up slowly it suddenly goes to "phase" (if you understand what I mean) and the sound disappears. I found out that one clutch plate ware broken so I replace all of them. No difference in sound.

Please help Im worried. This is my first bike and I resantly bought it.
Gasgas 2013 ec 300

Johan from Sweden

[hamilton]

Sounds about time to inspect/replace piston.
You got a little piston slap going on.

[Sjohan]

Ok so you can actually hear it's the piston?
I've ordered the size A piston is that bigger than the original piston or same?
This is the first piston replacement I'm about to do on this engine according to previous owner.
Thanks

[BSM2]

Normally I suggest to replace the piston with this sound if it has enough running hours.

However, I have a new 2013 EC300 with 400km/650miles on it and it is making the same sound.

So I assume it's a 'normal' sound.

contradictory?

[stabak]

Johan, in short your cylinder on the rear bottom side is marked with a letter corresponding to a piston size from the factory. Most probably an A but you never know. The correct way is to measure the cylinder's wear and order the appropriate size of piston according to specs and clearances....

[tonyraft]

Yep piston slap , my 2012 made the same noise with about 35 to 40 hours on it , I ran it up to around 75 hours and changed piston , noise gone , fitted wossner piston with at least another 50 hours on it since then , still all quiet

[Sjohan]

Ok Thanks all! i Think i get the parts many this weekend I come back and report after that!

[Sjohan]

http://youtu.be/EERGKJPmhZ0

Ok this is the sound after top en rebuild. New piston and rings etc etc.
I think the sound is a bit better.

[Sjohan]

Also when I had the clutch cover of I noti this. Is this normal?

http://youtu.be/USBNk2IoKYU

[thumperflipper]

If you think you have play in the basket, FIRST check the torque on the clutch hub nut to make sure it hasn't loosened (or not installed to spec). If it is within spec, then replace the parts my 07 manual calls "primary drive gear bearings AND bushing" that are under the clutch basket. Also the rubber mounts between the basket and gear mounted on the back of the basket can wear so check those too when you have the clutch out, not likely the problem in a bike 2 years old though.

My bike was making a similar noise, I thought it was the bearing under the pressure plate (manual calls it "needles bearing"). It rattled like a diesel engine with the clutch lever out, but with clutch lever pulled in the noise went away. So Mark at Gofasters looked at my video and told me what to replace. At least that fixed my bike's noise.

Also piston slap "should" go away or at least get quieter when the engine warms up. Did you find which cylinder you have, and got the right parts for the "A" or "B" cylinder? Were you able to measure it and the piston?

One other "rattle" cause always in my mind is the bellcrank hitting the inside of the case. As the RPMs come down and the governor closes, the stud on the bellcrank can hit the inside of the case. If you put the same size or smaller base gasket in this can still be (or become) a problem. Just look for a mark inside your case or see if the stud is resting on the case. Then make this mod:

https://www.youtube.com/watch?v=dI0fUUHaDjQ

good luck and welcome to the forum. hopefully someone much smarter than I will chime in