originally by Dino: copy & paste:
The new sleeve and piston set is very tight. It will let the rod have to take a very big stress during breaking in. And make the bushing worn fast even break if you make the rpm too high. So don't make the rpm too high when the sleeve and piston still tight. The most important thing is let everybody know that when the break-in process through. Then they just know when they can lean it to their heart's content.
We have ever changed the conrods production-line to make the bushing more thicker. So all the newest Dragon have upgraded conrods. I prefer to let every customer know what can be happened rather than hide them. Maybe my way make you worry. But to my consumer viewpoint(I'm still a customer to other manufactories ),I rather know every truth if they can tell me in advance.
Read the Instruction Manual,
...
I have a special way to check the break-in. Put a white tissue outside of the tail pipe. Let the smoke spray on it and open the throttle a bit. If you can't find any impurity but only oil,that means your engine is clean and no more fine metal particles out.
After break-in process,I will take apart it thorough. First I will check the con. rod bushings and pins. If there is a play,I will replace with new parts. Then I will check the bearing and crankpin. If there is any play,I prefer to spend some money to replace with new parts. I don't want to bet with full engine life and guess it still ok. In my opinion,I spend valuable time to run it a engine or you can say I bring it up like a pet. He/she have to work hard for me,I don't want he/she feel any uncomfortable. Have you ever run with a over-size shoes? Yes,it dose uncomfortable and maybe you will fall down.
Gentleman!~~Start your engine!~~
hope that helps!