Is that a chunk of carbon or some form of metal? If it's metal, I'm curious as to where it came from. I found an EGR pipe flange nut in the combustion chamber of my FL2, which required a replacement head and piston, but the bore survived with just a hone.
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Timing the engine is easy. You simply use the pins. The cam chain is timed by lining the dots on the sprockets with the different coloured links on the chain.
The manual shows everything you need to know.