a classic problem

haven't had this problem in years, the classic trembling or shaking of your fork and front end of your bike while applying your front brakes,

what can i do to avoid this ?

i'm more concern in the long run, i don't think is good to give my fork that extra strain

Any extra strain isn't going to hurt the fork. The classic suggestions apply:

• Make sure your headset is tight.
• Check your wheel for trueness. If untrue, true.
• Toe your brake pads in.
• Change brake pads.
• Make sure your quick release is sufficiently tight.

Any of those could be the source of your problem.

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