Noise in pipe after rebuild

[Ed5786]

Well, the top end was badly worn when I got it. It ran ok, but the cylinder walls were scored, along with the piston. So I bought a pro x piston, and sent it with the cylinder to millennium for repair. Now that it's. ack together, the 42pj was to lean, I had the mixture screw not even a turn out. And it had a bog between mid range and top end, so I raised the needle. Haven't had a chance to do plug chops yet, just been going by feel. Both changes made were positive

[Friedom]

Cool. In that case I hope you richened it enough!

"Fun Wheel Drive"

[Ed5786]

That's why I'm worried about this little tingy ticky sound I'm getting in the expansion chamber. It could be nothing though and I'm just paranoid. But it seems from what I've seen others jetted at, it's close

[Friedom]

I agree. Didn't mean to take over your thread, I just know that my brand new rebuild engine had catastrophic failure and while it was likely my fault, I didn't have any obvious issues. Just that it was loud(which got better with putting a stock pipe back on) and seemed to have this incessant ringing sound!

"Fun Wheel Drive"

[Ed5786]

I was afraid of an air leak somewhere, but it idles fine and doesn't hang at all. Just the occasional PINK on the decel, but just when it free revs with no load. Maybe unburned fuel igniting?

[Friedom]

Sounds like it's plug choppin' time.

"Fun Wheel Drive"

[Ed5786]

I am thinking is normal and just due to the extra compression it has now. I just fired it up and richened up the mixture screw to the point it didn't want to really rev and it didn't do it. Backed it out to where it was crisp again (which wasn't much), and the TINK TINK TINK on decel came back.

[Julien D]

Jetting is a process. Make sure the build is solid, pick your oil ratio (I strongly recommend 40:1 or more), and jet for it. Jetting by what you've seen is just guesswork, and doesn't do you any good at all. If the pipe was added after the rebuild, the sound will be different, obviously. So far I'm not really clear on that. I can't see mistaking a 2 stroke ping sound for something rattling around in the pipe. That's a stretch.