Super, glad you found it. And for the record, I wasn't trying to bust FPV's chops, just pointing out Ed's reasoning (I sincerely hope) for his comment.

 

I am really glad you found it. If you believe that there are smaller pieces of it floating around, and are't going to split the engine, inspect very carefully.

The rag running over the sand casting most likely spread fibers.

If you run it, one thing you will need to watch for is fiber debris sticking in the oil relief valve. Symptom would typically be oil pressure that drops off significantly when hot or little to no oil pressure. It tends to happen right after a start when the relief valve is pushed to bypass then gets stuck.

If you didn't start and run the engine, it's highly unlikely that it has gotten to the cam plate (will depend on how much cranking you did) but if there are fragments in the engine, you might want to remove the cam plate, pull the pipe plug (one not usually removed from the bottom of the case), spray down the inside of the crankcase, spray down the pickup from the cam chest to the oil pick up - it should all drain out the pipe plug - tilt toward cam side. If there are fragments too large to move through that passage from the flywheel side of the case to the pipe plug area (it's very small), a battery powered oil transfer pump or similar to suck out the stuff in the bottom of the case might work.

To check for a clogged passage between the flywheel side of the case and the pick up we used to tell dealers to pull the pipe plug & pour in a bottle of light fork oil. It should run out right away as it's going in. Should come out quick and get about as much out as went in. If it's not coming out and you put compressed air into the bottom of the case where the pipe plug was removed while covering the hole where the oil pump plugs in, and then it drains, there is debris clogging the little passage. If the pump is installed, you just have to pressurize the hole where the pipe plug was removed.

Something like this might work if trying to manually suck stuff out. (you can find cheaper versions on Amazon).

https://www.northerntool.com/shop/to...SABEgKuzfD_BwE

You will have to make the call based on your inspections, how much you cranked it, and the condition of the rag.

I'm throwing a lot out there - let me know if you have any questions.

 

 

If that used to be hole free and a symmetrical shape, personally I would have both cylinders and pistons off and inspecting and cleaning as I mentioned above. If the holes match up perfectly and it was that weird shape initially - maybe a little less worried but still doesn't look good to me - I'd still be inspecting more.

It get's scary for clogging a piston jet etc if you have a lot of fibers in there that wouldn't be there after a filter removed them and they make it through the bypass. I have seen clogged piston jets from fibers and that's ends up being jets, pistons and bore to next oversize. A symptom there is suddenly slightly higher (than the bike always had) oil pressure at idle off as they don't open and bleed off because they are clogged. (At least that's what we observed when it happened)

 

Also - thank you for the compliment. I didn't mean to come across so gruff initially with the two threads.

 

Good job bet you feal better.

 

 

Here is a picture of the sump pickup in the crankcase.

 

 

That hole is where the oil that is fed into the flywheel compartment is sucked back up by the oil pump.

That is the small passage that leads to the return side of the oil pump. The allen plug you remove from the bottom of the case is how they drilled to connect that passage to the cam chest where the return gerotor sucks it up.

That is the passage that I was referring to if it is clogged with the rag, fork oil won't come out if you pour it into the crankcase with the allen plug removed. If it's clogged, the air pressure introduced into the allen plug pushes the debris back into the flywheel compartment and the oil comes out.

If you believe it's ultra clean and you didn't crank it enough for the pump to really suck anything up, you could leave the cam plate and pump in, and just remove the allen plug and flush everything out - spray inside flywheel compartment and it should drain out the allen plug hole - tilt toward cam side or at least have it level. Also spray up into the allen plug hole.

Then fill with just cheap oil, leave filter on, run engine for a bit - take it around the block and do an oil change with good oil and a filter.

I have done lots of oil changes with cheap oil that meets spec after gasoline flooded engines and then just change oil and filter with good stuff.

You have eyes on so only you can make the call. If you just clicked it over or rotated by hand it won't be in the pump yet. If you cranked and cranked with the starter it's possible. I don't know how much it was cranked with the rag in it and was trying to be safe than sorry with advice. However, if you have it half apart with heads off - removing and inspecting tensioners and pump is only a little more labor.