I have a 1985 Honda Big Red that I am having an idol problem with it. When I start it and it is in nuetral it will idol quite high, so high that if I am not holding the rear and front brake in it would probly flip over on me. But once it is in gear it will idol just fine. I am not quite sure where to start with this so any help would be great.

I was thinking of starting with rebuilding the carb and then go from there.