I have never used a needle bearing for a connecting rod little end. It's fitment in the little end and the wrist pin through it are great. But it seems like there is nothing keeping the needle bearing from sliding around on the wrist pin and out of the little end. There is enough space for the bearing to come completely out of the little end and hang out on the wrist pin on either side of the connecting rod. The crank came with the needle bearing and was not specific to the 45mm piston I am using with it. And to be sure its not pressed in. It came with a bread tie holding it in place.
Should the wrist pin be wider? I assume the crank was for a stock 38mm piston.
If not what prevents it from sliding around in there?
This motor is a Puch e50 and I am one of those guys who just bought the treats 70cc kit with the 21mm Dellorto. But don't worry I wont ask any of you how to tune my carburatore lol.