[DaveO430]

What about if you pull the choke? Does it increase the idle speed and cause it to hit on the right side cylinders? Try turning up the idle speed, if it starts to hit then it may be the carbs are just way out of synch. There is no timing adjustment on an 1100 BTW.

 

[DaveO430]

Just no way around it, you are going to have to pull the carbs and do some cleaning.
Your clymer manual probably covers 1000s also, they have a points ignition and you can set the timing on those. 1100s are electronic ignition and there is no adjustment.