are there anything special about stem bolts that I should know about? Can I get replacements from the hardware store, like regular m8 zinc plated bolts?

Ah, quill stem.
Don't take for granted that it's a M8.
And quill stem bolts tends to be disproportionately tall.
Apart from that, go ahead.

Metric usually a socket head Cap screw, and Yes various thread possibilities (my Cinelli Is different from the Nitto
and both different from the threadless top bolt ..

I dont know anything about your hardware store inventory , they carry Stainless steel & metric?




'/,

Agreed that stem bolts (and many other bike fixtures) are not always common ones. Both thread and head might be unique to the stem. This is why actual measuring and/or having a sample in hand when looking for replacements is a very good idea. Andy

sorry, I meant m4.. haha... it's a threadless. but in any case, it's not relevant anymore, because I missed the bid for it on ebay. it was a zipp stem without any bolts, and a broken bolt stuck in it. I could've scored a nice deal on it. oh well..

Common bolt into an Aheadset Star Nut is 6mm .. I have no Idea what Zip chose to use.

Clamping bolts are usually harder than what is commonly available in stainless.

There are many different alloys of even stainless steel.. Be specific..