your chain isn't too tight is it? what size rear sprocket you running? your brakes aren't dragging? tires inflated to the proper pressure? axle bearing greased and adjusted so they aren't too tight? also the dax will need to be broken. All of these 2-stroke engines will run poorly until they get about 2 or more tanks of fuel run through them. I'll run about 20 to 1 for the first tank then I go to 30 to 1 after that. My dax engine had 2 base gaskets and I removed them and played with the thickness of the base gasket to make it run bettee along with that you will have to make sure you don't hit the head with the piston.

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