I would be suprised if it was the reeds. However, I always used Hy-tech competition reeds in the X7 with no probs. Check the opening distance for the reeds isnt too wide as this can cause extra fuel to be let in but it can crack the reeds due to the harmonics! I had a set shatter on me making the bike a very sluggish 135.5cc bike instead of a 271cc flyer!!

Just a thought! Hope you get it sorted.

Andrew