!!!!!!!!dirt bike problem!!!!!!!!!!!?

Tell your dad you ride your friends bike all the time.
Bring you dad with you the next time you go riding, to show him you know how to ride.
Make sure you have all the proper safety gear - helmet, goggles, gloves, MX boots, chest protector.
At least a helmet, goggles and work boots - no sneakers.
That will show him that you take the necessary safety precautions and are responsible.
If you don't have "your own" helmet, goggles and boots - forget about your dad letting you have a bike.

...you get one yourself...don't rely on your dad..every young biker goes through the same thing...