sparks coming out of exhaust

Just fitted new mugello 225 with 30mil carb, using my old ancilotti race exhaust.
Done approx 200 miles, with no probs, but been told when accelerating a few sparks come out of exhaust,
could this just be, old carbon burning off or something more serious....
cheers Gary
Done approx 200 miles, with no probs, but been told when accelerating a few sparks come out of exhaust,
could this just be, old carbon burning off or something more serious....
cheers Gary