Engine slight "shiver" at idle- normal?

[Vitalie]

Ok, while I am waiting on parts to fix my speedometer I will post here something that seems not right to me. I noticed that at idle with all the accessories off my car "shivers" very little but enough to feel it at about 5 seconds interval. It feels like a little kick or something.

Here is what I did for tune up so far:
New alternator (the lights were flickering and the car was literally hopping in traffic)
New timing belt timed by spec.
New air filter
New spark plugs NGK gaped to 0.28
New spark wire set.
Cleaned the throttle body and the EGR channels (440 gone)
I checked the timing is set to 5'

I ordered a distributor cap with rotor that I intend to replace but so far nothing changed from before the tune up begun.

I posted a on YouTube something I tried to catch the problem on video. http://youtu.be/NTkipnBrrx8

Well at this point I am leaning towards that is normal. What do you guys think?

My car is the chevy tracker 98 2wd, 4door, 16v. 5sp
Thanks