Hey guys, so I recently decided I want to put a new head on my son's Tao 125, I got it pulled apart and went to install the new head when I noticed that the old head had the gear opposite from everyone on YouTube and also opposite of the new one I got.

I have the flywheel turned to the T marked with the line, piston is sitting perfect TDC but im wonder is the timing gear off by 180 degrees? How can I tell which position it should be in?

I guess what I need to know is when I'm at TDC and the rotation starts, the head should be just opening the intake valve, correct?

Also from anyone's experience do the Goofit pre-built heads on Amazon need valve adjustment? Or do they come pre adjusted?

This quad has been having trouble running since i bought it, could this timing issue be what's causing it or if it was 180 degrees out would it just not run?