I personally have seen the Weisco piston Fail three times on the same motor (2010 CFI-4 800 Dragon)... This was my sled that I sold to a friend and helped him rebuild it 4 times. Here is the story:
-First, I lost the stock pistons from I am guessing a lean or det issue. Burned a huge hole on the exhaust side of the piston. Then replaced the cylinder with a Millennium Tech reman, and installed the Weisco replacement piston kit.
-I sold it to a friend with the motor rebuilt 0 miles. He had the first failure with the Weisco stock replacement pistons, which was the infamous piston skirt snap failure which took out the whole motor in less than 250 miles.
-Then installed another cylinder (Another reman from Millennium Tech) with the Mtntk fix kit and repaired the hole in the crankcase from the piston skirt going through the case. Then, the fix kit cold seized (I'm assuming) even though the throttle wasn't touched until coolant temp was up to 125*. But he had to get on the throttle hard right from the trailer to climb a large mtn. So we were thinking that was the failure cause, cold seizure because it looked like the pistons swelled evenly and scored the cylinder.
-Then Mtntk did a warranty(props to them) on the pistons and those lasted about 500 miles. This time, we were very careful on warmup and throttle until it had been ran for an extended period of time. It seized the same way as before, but after riding all day. It all of a sudden squeaked both pistons. This time when we opened it up, the PTO rod bearing went out too.
-All the while it had the Dynotech PCV tune on it to prevent the infamous lean mid range condition. Obviously this was a lemon motor, but the fix kit and PCV still didn't fix the issue with that motor. I haven't had any experience with the Wossner pistons, but heard they are doing well.
This is my personal experience with forged pistons... Got real tired of rebuilding that ticking time bomb. Lets just say my buddy isn't riding that lemon anymore either.
