Back tire physics

[kolton3.5]

Is it just me or does it seem not very realistic when going up hills that the back tire becomes super squirrely no matter what you try, the best fix I've found is just to keep as straight as possible but that isn't always possible, trying to figure out if its a bike thing or a track thing. Thoughts? 

[PizzaChet]

Try partial throttle. It's the secret.