Guys,
I am almost at wits end with this one so I need one of the gurus here to point me in the right direction.

I have a 2011 Speedmaster and since new (even before any changes were made) there has always been a hesitation just above idle that can cause you to stall the bike when taking off from stop. The revs start to come up, but when you start to load the engine up by letting out the clutch, It seems to have a flat spot in revs and if your not onto it quick enough by applying a lot more throttle, you can have a very embarassing moment as she stalls. Also if you blip the throttle between downchanges, there are times when a blip does nothing to the engine revs at all.
Now I have made some changes but would like to point out that this has always been on the bike since new and even after changes. I feel as if im chasing my tail with this problem and may be looking in the wrong area for a fix.
Changes to date have been:-
Fitted Aftermarket Silencers
Remapped to 20456 with Tune ECU
Removed SAI and plugged heads. (SAI solenoid and piping to airbox is still in place although plugged).
Balanced TB
Reset TPS
Done 20 min tune
Tried setting TPS to 3% to fool ECU (didnt really work) so back to 0%
Disabled O2 sensors at one point but no real difference so back on again

Another part to this story is when I took the bike in for its first service. (only Aftermarket silencers fitted, nothing else done at this time). They serviced the bike and balanced the TB. They reloaded map 20455 (which is standard tune). After they took it for a test ride, the mechanic commented on the flat spot. I said "yeah its always been there and im used to it".

I think going down the path of changing fuel maps, replacing TPS etc should not be required as I think it may be a simple fix. The issue I have is that the dealer may not be to keen on helping me since I have done some of these mods, and warranty may be an issue.

So my question is, has anyone else experienced this problem with the EFI 865 engine and if so, how did you go about fixing it.

I would just like to hear some thoughts and hopefully get on top of this so I can enjoy riding my new machine.

Thanks Trev10

2011 Speedmaster Leather tank Strap, Leather Saddlebags, crashbar, short sissy bar and rack (2010 model does fit), Aftermarket pipes (OuterCycles short) nice sound, Engine remap Tune 20456 minus SAI & O2 sensors, Removed SAI completely