i have a 50 with pretty much stock gearing. have a 38 tooth in the back and i am running a 88 kit with race head. my problem is that my bike is topping out of its top speed way to quickly. i am racing at havasu and i heard their track is very fast. my question is what would be a good front sprocket? 15 tooth or 16 tooth? also, takagawa's sprocket has holes inside of it. Will this effect how it works compared to one with no holes?