What is the best after market exaust for a 250 ex?

 

I have an FMF MegaMaxII, vented airbox lid, UNI air filter, and of course a rejet. Perked the little bike up quite a bit.

 

You might want to look at a White Bros E-Series. It gives the quad a REAL nice sound, and added some kick to the motor. I have a MegaMaxII on my recon. It gives it nice power, but the E-Series sounds a lot better, and about the same boost in power. You can probably find one on ebay for cheap. Do yourself a favor, get an e-series, you'll like it.