Carb or Air leak from that Tube , or Air leak on the Motor , Learn About Leak Down Tests And jetting and you will have some work to do
Well depends on who you want to listen to there , I'm not going to tell you to listen to me over your Father , But Has he owned one of these type of machines for over a Decade ?
most of us here have ton's of expirence with these machines spacificly. I have been through every square inch of these quads as have many other guys here.
You should tell them you can learn by doing this work yourself , Heck show them the Site and what we do here , It might give them a better understanding about what we do here , Tell them you want to learn to do this so you Save money and can apply this Knowledge Elsewhere in life ! .