hi, my bike is a mod bike for trials and i just got a new bar and stem for it. since fitting it on, the front wheel has been acting weirdly. You see when i apply front brakes full throttle, i shake it forwards and so, and i find that its kinda loose looking. My theory is that the headstes are strange and dont allow the fork to stay firm witht he frame. Can anyone suggest anything to me, (no dont give me any sites on how to...) and my bike shop in town is closed for a week! uhh if u can tell me what i can do to solve the problem itsd be most appreciated.