sertac74

Hello, i have test fly my saito 125 with showtime.Last weekend. I fine tune the engines low and high valves and fly the plane. Flys smoothly but i feel the engine is under powered . When trying vertical climb plane goes about 10 meters up and the rev starts to decrease then plane drops.. There should be some tune problems i think. I dont whant to think the total power of 125 ends there , it should go better. What do you think about when climbing rev starts to decrease then lost of power.

I also have the fuel in the tank is black after flying.(orginally redish) I know the presure line press the burned oil to the tank but is it normal the output of the burned fuel black oils. When flying engine has too little smoke out from mufler. Sometimes it is not visible, but black oils come out to body of the plane and to inside of fuel tank.