07 RMZ-250 Jetting with new exhaust

[sniper250]

I just picked up a pro circuit TI-4 GP full exhaust system. I will be putting it on my bike in the next day or 2. Will i have to change my jetting when i install it?

[455]

I just picked up a pro circuit TI-4 GP full exhaust system. I will be putting it on my bike in the next day or 2. Will i have to change my jetting when i install it?

Run it stock

[mike27t]

Old thread bump..

Just installed the same system, bike is running really good on stock jetting. Pro Circuit suggests changing the main to a 162 (from 170), needle position to a 3 (from a 4) and the screw position to 2.25 (from 1.5).

Not even close to being an expert in this area, but if I understand correctly I might be running a little leaner than I should be with the stock jetting. With the hotter days approaching in SoCal should I rejet? What do you guys think?