fuel needle

[TRX400EX02]

I bought an FMF Q2 slip on for my 400EX. I also bought the FMF Power-Up jet kit. In the jet kit directions, they tell me i need to swap out the fuel needle, for the one that came in the kit. Is this necessary? Im asking because I have almost stripped the head of the screw that holds the slide in place. What are the benifts/losses of doing this fuel needle change?

[kc8pnd]

I may be wrong, but the needle will compensate for the increased airflow from the new exhaust.

[wcbomb]

:( Yes, you do need to switch the needle for the jet kit, stock needle won't work with dynojet, it will run, but not like it's suppost to. Try putting the carb in vise so you can get more pressure on the screw. Those little soft screws are a pain in the *****.