It goes gummy after a while, IIRC. Anything that becomes sticky is exactly wrong for a STI shifter. You'll need to keep on flushing, with something like WD40 this time.
If you study the pics in
this post, you may be able to see why...
The shift barrel is held in place by tiny little pawls actuated by little hair springs, and as soon as their pivots get sticky, it's all over.
Originally Posted by
frantik
damn fancy new fangled parts.. i dont like bike technology i can't take apart and service.
Ergos are the brifter for you. Simple enough to easily understand, overhaul, and be reliable. They wouldn't give a damn what you lubed them with.