Front Disc screeching/vibration .. help please :-)

[NickinBattle]

Front Disc brake(Shimano) makes dreadful noise/vibration just at the ‘bite’ point where it stop the wheel (final 2 or 3 cms of rotation on the rotor !
Only started a month ago No luck in sorting it ! .. have had pads, rotor and caliper all replaced and it makes very little difference (all are clean, aligned and functioning as they should)
Absolutely no problem on the rear.
Don’t know what to do or try next. Help please 😊
(someone did suggest its vibration coming up thru the forks into the head and its loud as it travels thru bike frame tubes .. head not set up properly or worn ? )
Nick

[ReapThaWhirlwind]

It sounds like you have too much distance between the pad and the rotor.

The amount you should have is barely 1mm.

This is the likeliest cause based on what you've provided.

The only other could be decay on the system. Meaning, the metals have been weathered too much, finely oxidized, softened, etc.

Replacing the brakes entirely will be your only option there.

[NickinBattle]

thankyou for your advice ... much appreciated !

[Criminal]

Did the problem start while on a ride? If so, did anything odd occur on the ride that may have affected the bike in any way?

Since you stated everything was replaced with properly installed parts so you should be able to eliminate the braking system. As to the alignment being checked, what exactly do you mean for clarification purposes?

[Flowrider]

Others on here have far more depth of knowledge than me, but is it as simple as accidentally spraying something like WD40 on them?

Purely a shot in the dark here...

[meamoantonio]

does it sound like this *tsssssst tssssssst tssssssst*? if it matches you have to align your brake calipers to the rotor, loosen the bolts on the caliper then squeeze the brake then tighten them, if the problem persists you might have a slightly bent rotor which can be easily fixed using a rotor aligning tool. hope this helps!

[rydabent]

Everyone knows that when you mount rim brake pads you leave the pads looser where the rim enters the pads. I believe that can hold true to disc brake pads too. Thin shims can be added to the back of the caliper where the disc enters the pads.