By: news (offline) Monday, 03 November 2008 @ 07:54 AM ICT
We are quite happy with the stock jetting on the 2007 model of the Yamaha YZ250. For the 2006 Yamaha YZ250 the engine would ping if you changed to an aftermarket exhaust pipe, so we used to change the needle.
For the last years model, Yamaha switched to the same needle we used in our 2006 model. We do add one tooth to the rear sprocket to help get more drive out of send and help get to third gear quicker.