2003 Yamaha YZ250R Jetting Help (Pinging)

I just bought a 2003 Yamaha YZ250R Two Stroke.My bike is jetted stock:178 main,50 pilot,N3EJ needle,clip 2nd from the top.The only modifcations I have done are a FMF fatty pipe with a FMF spark arrestor.I use Dumonde Tech DTP full synthetic oil at 50 to 1.I just replaced the top end and everything looked good.I ride mainly at sea level to 3000 feet.My problem is the bike runs great at the low end but it's severly pinging at the mid to top.I tried moving the needle clip around but with no luck.I know these bike run great with the stock jetting :D

Mines pings a bit on the top, you need to run race gas more than change the jetting. I have good luck mixing pump and race 60/40. I did lean out my jetting a bit, but I'm at 6000ft.


thanks for the info.


Thanks, I'll try that

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now