I think I have a problem...

...no, I know I have a problem!

Riding without a helmet (I know, I know), to listen for odd noises, I distinctly hear kind of a rattling vibration sound coming from the cylinder area. The noise wasn't there before I did the BB kit.

So, after a short ride this morning, I changed the oil to see what it looks like. Fine metal shavings, and lots of them. More than I think would be the result of breaking in the new piston and cylinder.

I don't know what could be causing it. I lubed all of the parts up real good before reassembly.

There's only a couple of things that it could be as far as I can tell. Either it's the top end of the connecting rod, the piston where the wrist pin goes through, or the rings themselves.

I haven't done a compression test as it is running strong and there's no smoke, but I'm afraid the thing is going to grenade at some point. Not really looking forward to tearing the thing down again, but I'm afraid that's where I'm headed.

I'm going to put some new oil in and ride a little more. I'll take a look at the oil and if there are more shavings, it will be "off with it's head!" (and cylinder, and piston).

Sheesh. I should have left well enough alone...

Camchain and/or cam chain guides come to mind.
Be sure to post what you find. :)

YZEtc wrote:

Camchain and/or cam chain guides come to mind.
Be sure to post what you find. :)

Curious. Why would you suspect the cam chain or guides?

I imagine a strange noise and an abnormal amount of shaved metal having to do with something being sawed through.
That's just the first thing that comes to mind.

Hopefully, there is no problem and you're being paranoid.
If you do take it apart, let us know what you find.

YZEtc wrote:

I imagine a strange noise and an abnormal amount of shaved metal having to do with something being sawed through.
That's just the first thing that comes to mind.

Hopefully, there is no problem and you're being paranoid.
If you do take it apart, let us know what you find.

Will do.

The noise/vibration/rattling is only evident at certain RPMs. I'm guessing somewhere around 4k to 7k. I get it on accel & decel. Very prominent.

Ok. As I posted in another thread, I changed the oil again after 100 miles or so. I wanted to see if there was still evidence of unusual wear, as in metal shavings in the oil. Drained the oil, let it settle out for about an hour and then slowly poured the oil from one clean tupperware container to another (thankfully, I'm not married, so no admonishment for using the tupperware).

Guess what? No metal shavings! Clean as a baby's butt (after you clean the baby's butt, of course)!

There's still a noise, but maybe that's just the difference between stock and the BB kit. I don't know. I'll just keep riding it. Runs great!

You wouldn't expect a lot of filings from a new piston and rings but?
Never hurts to pull the filter out and see what is in there, see if the stuff sticks to a magnet etc
I would expect an aftermarket piston to change how the engine sounds though
Cam chain slippers are neoprene so they would make a lot of black rubber stuff before they make steel filings, likely you would have a loud Chaka Chaka kind of rattle from one side of the motor if that were an issue

the crank isnt balanced for the bigger BB piston so that will cause vibration