Ducati Monster 600 Build 

Red with white stripes is the best color for Ducati.

If anyone is interested, did my research - its definitely first generation monster engine piston slap.

Kinda late response, but that's just the sound a dry clutch makes.

I have exactly the same sound, mine is also an 600 from 1999. Any updates?

I have been to a secondhand partshop. the man heard the sound and said it was somthing he heard the sound more often on this type motorcycle. the sound can be more over time, but it cant do any harm.

Congratulation for your nice job. Don't worry about this verry well known bell sound comming from the front cylinder. All early models of 600 make that sound. It is piston slapping due to the casting pistons replaced on later models by forged pistons. My 600 Monster and my 600 SS make both the same sound. I have checked on a spare cylinder and spare piston within factory specs dimension and i can reproduce the bell noise by moving the top of the piston slightly in the cylinder. So don't worry, ride and enjoy this verry nice bike. ;-)

thanks, it nice to have it confirmed.

Look at this Article, it says that the later models are using cast pistons. The earlier models where build with forged pistons (the slappy ones) which suggests that they are better build. Forged pistons are more more durable If I have understand it right. The only thing I don't understand is why the forged pistons make that sound. www.bikeboy.org/600monster.html