When should i change the top end on my yz125 because i race an i don't know when should change it?

Question

When should i change the top end on my yz125 because i race an i don't know when should change it?

Answer 1

On my kx250, the book says, every 7 hours, or 3 races. For top top performance.

    I am on 60+ hours on it, and it still beats alot of the other bikes I race.

Answer 2

if you race, you should change your top end regularly to keep the engine able to perform to the best it can.

Unless you are a pro, and pros will change thier top ends every race, you will not need to change your top end as much.

I would say about every 10 races or so you should change it, if you are racing a lot with it. but if you race like I do once in a while, then you dont have to change it out as much.....