Warning some speculation on my part and some fact. The valves, or maybe just the exhaust valve in the 1400 is a welded valve. Piaggio hasn't said anything about it but I believe the weld is known to fail, or at least I have heard that. Mine, before I owned it failed at 543 miles. The service manager wouldn't tell me what failed but the engine locked up suddenly at speed while the store manager took it for a spin before my arrival. I am inclined to believe this failure will happen within a short period of time. The replacement engine ran just fine with no issues for 17,000 miles before I had to pass the bike on. I still miss it but it was just too much for my ancient body. It could sure eat up the miles, I rode it across much of I-80 in Nevada at 85 to 90 mph. Ride it worry free.
kk