I finished assembling a stratocaster from Warmoth parts about a month ago with the help of a guitar tech for some aspects. I am having a problem with the bridge/tremolo unit. (it is a modern 2 post American standard style bridge)

Firstly, it seems incredibly sensitive and often bends sharp when I palm-mute on the bridge. In addition, when I bend one string, the others go out of tune quite severely. (e.g. when bending the g string up a tone, the b will go out of tune by a semi-tone making unison bends impossible). Upon using the tremolo, it goes out of tune when divebombing, downward bending etc and will only go back into tune if you pull it back up and reset it. Finally, when tuning it fails to stay in tune: upon changing to Eb tuning I had to retune about 6 or 7 times before it stayed and vice-versa.

Any help would be greatly appreciated

The knife edges are blunt. This could happen from either years of playing; adjusting string height with full string tension (that's over a 100 pounds of tension rubbing on those knife edges); poor quality bridge/materials or a combination of any one of those things.

This happened to one of my guitars which was £250 new so it happened to be a combination of all three. I've had to block it off as it's an OLP and there's no bridge to replace it. You need to replace yours with the same style bridge and get that guitar tech friend to get it installed at the right string height.
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