250cc Power Characteristics

[Chakka]

I have read a couple magazine articals that state the 1977 250 Motor featured better low end and improved trackability over previous years. Many 77's came with Lectron Carbs, could that be the difference or is the porting improved as well? I was curious if anybody has ridden both and can comment.
Chakka

[Big Mac]

I think KTM revised porting slightly and went too a slightly heavier flywheel in '77. I haven't had a '76 motor apart to compare but have read in several places that the '77 400 motor had flywheel weight added. Not sure about the 250.
Mac