I bought myself a brand new 2014 crf 150r that i worked all summer for (totally worth it). Wondering on how often i should replace the top end, And also how hard that is. I'm about 6 foot and 200 pounds. Dont race but dont ride it easy either. Any tips on how to set up shocks and how often to change oil/clean air filter would be appreciated. pretty new to race bikes so anyone with expirence that has insight please leave a response. I want to do the top end myself. Have worked on motors before but not one this expensive.