Well you know Nitto AL drop bars? Aluminum bar is covered over by aluminum jacket(!?) where you clamp down with your stem. This aluminum jacket has a slit-like hole to allow some gives from clamping pressure you put on.

When I put on my drop handle, this slit does not get covered by stem leaving it exposed. I think I was compressing the edges of this slit making it creek. If I use Technomic stem (25.4mm right?), this slit will be always covered unless you use very odd angle.

Thanks goodness, I figure it out quickly. But too bad, I can't use that handle bar. I am back to a straight bar again.

T