SO I had my sick bike parts shifter kit on my bike and i'd say have about 250-300 miles on the bike by now. I haven't been to easy on the bike while changing gears and such because i wasn't quite used to it yet so it would jolt a bit after changing gears and such (I do let go of gas and try to gradually accelerate when changing gears). Anyways, now when I go and it seems to be doing this under hard acceleration or strain on drive train. The bike would go, then it would feel like the freewheel of the derailleur would slip then catch again so it would be like the bike is having hiccups. The problem isnt constant, just once in a while. Probably at least 5-10 times a minute of city riding? I'm going to stop riding for now, if anyone knows how to fix then please let me know. If not do you think a bike shop could do a rear wheel overhaul? Let me know please. Thanks