I have a Romainian SAR 2 with what has to be the worse case of trigger slap ever. What causes this, and more importantly, how do you fix it? I've seen it discussed before, but never heard how to fix it. It's actually painful to shoot...

http://ak.ar15.com/forums/topic.html?id=50352

Due to the sometimes indifferent US internals used in the SAR series the disconnector will impact the trigger as the bolt carrier moves back during the recoil cycle causing the sometimes painful trigger slap.
There are several cures:
1) Install a US-made stockset (like K-Var's black polymer) so you can legally replace the US trigger & disconnector w/Romanian AK-74 originals from Tennessee Guns ($20). That's what I've done with my SAR-2s.
2) Grind off a *small* amount of material from the bottom back of the disconnector until it no longer impacts the trigger during the recoil cycle.
3) Install a better quality set of US internals.
HTH, keep us posted...
Tomac

Thanks! I have a Romanian trigger and disconnector, as well as a U.S. made handguard set now all I need is the stock. I wasn't sure if this was a problem with the U.S. parts or just the way these guns are, as none of my other AK's have this problem. I've already had people tell me to just put a short length of rubber tubing over the trigger to cushion it, but that didn't seem like the best solution.

Thanks again!  

Try the AK-47.net site.  Look under Romanian AKs section...there are several links (with photos) of fixes for trigger slap.