Flywheel weight?

On a one two five it may make some difference but seance you have to stay in the upper Rpm's anyway to get power, it will smooth out the "hit." I am about ready to out grow mine and I don't have a FWW on it. I ride woods and have to work it a lot to keep power generated. I will be moving on to a larger bike someday soon and if I do a FWW is one of the first mods I will make to it. For the larger displacement engines from what I have learned is that it smoothes the 'hit" and makes the power more manageable. Some other things you may want to look at are jetting, pipe and silencer mods. Just a thought.

Good Luck!