It seems to me the cheapest and easiest mod I can do to help give some kick to this bike is a $10 front sprocket. What tooth count do you recommend?

 

Many of us try the 13 successfully. Not too much mention of 12T. A 12 could be small enough to cause excessive wear on the chain slider so watch for that.

If the 13 isn't enough and you're thinking 12 would be better, consider upping the rear sprocket.

https://www.kawasakiforums.com/forum...-length-42553/

 

thank you, just ordered a 13t!

 

You'll like it.