Flat spot


Is anyone else suffering from a bad flat spot at around 25-35mph when hitting the gas in 2nd or 3rd?
Ever since my bike went in to the dealer for a 4,000 mile service, this problem occured, and now the dealer can't fix it!
Driving me crazy, can anyone help?

I think we need more info to help is your busa stock or does it have a pipe or power commander. My busa had a flat spot between 3 and 4 thousand rpm remapping the fuel curve on a Dynojet 250 dyno solved the problem but I have a Ti force pipe and power commander and my busa is 1498cc. Knebnr
What are the chances that they messed with the cam chain? If they did there is a chance that they put it back on wrong. If they had to remove it for any reason it is posible to put it back on one tooth off and the bike will run good enough that they wouldn't notice. That is what happened to mine when they did the cam chain tensioner recall. Attached is a copy of the before and after dyno run. The low HP run is with the chain one tooth off and the high HP run is with it installed correctly. If in doubt have them Dyno it for you.