Moped Army

The truth is moped lifetimes are entirely arbitrary. A kit could potentiall increase life since it's essentially a new engine topend. If other parts are worn already they may break from the increased power on it, but if you install the kit right it should be OK, treat it well. Carb & pipe and tuning upgrades wont hurt the engine as long as you keep it tuned right
Anything that does break you can fix or replace with something better anyways.

realy go ahead and start putting on upgrades, just be sure to keep a good oil ratio and keep the air/fuel correct keep a good air and fuel filter in and dont go doing stupid things like wheelies into parked prius's and you should have that moped last quite a while.