The carb question is a tricky one, someone with more knowledge in this field should chime in shortly but below is what I use to determine if the carb is adequate.
Put a vacuum gage on the intake and see if you have any reading at WOT under load, if the gage is reading vacuum then you probably need to move up a size, if it is zero, pull your plugs and read them then adjust your jet size accordingly.
Again this is my way of doing it, as others will probably have a more accurate method.
The engine should run ok so long as it doesn't lean out, I currently have a 650 on mine and it is basically stock I just moved up the jet size until the plugs looked good and everything else was ok.
Last edited by pcdimis; 11-04-2013 at 11:04 AM.
Reason: Re-read the question****