Carb/Jetting for the FMF pipe? and...

I have a brand new 2003 xr50 and was wondering if anyone could help me out with a few questions.

1. Stock engine with the fmf pipe and a uni filter. - How should I set the carb/jetting for optimum performance. It seems to bog and almost die when I get on the 1/4 to full throttle position quickly, when I get on it slowly it's fine, so I know something's off, I'm just not very experienced with 4 stokes or 2 for that matter. I emailed fmf about jetting for the pipe and they haven't replied.

2. Are ignition boxes a good mod? And if so which one is the best? My friend has the takigawa hyper cdi box, but I've heard there's a blue box that kicks ass, do you know what I'm talking about?

3. Any other inexpensive mods I can do besides, tall seat, joker bars/triple clamp, big pegs, new tires, uni filter, pipe, and skid plate?

4. I have to set my tank on reserve in order to get gas flow, on regular position the gas doesn't flow smoothly, anyone else have this problem? Any idea what it is?

Thanks in advance for any help you can provide.

I may be able to help with #1. When I just openened my airbox on my XR100 it got REALLY lean. You could try a bigger main in there, just for kicks. You could check the plug to see if the tip looks white.

I just switched from a Fast50's exhaust to stock(Fast50 exhaust was too loud). I experienced bogging when trying to open the throttle wide open quickly from idle.

I played with what I believe is the fuel screw(screw below idle screw)...maybe it's the air screw...but who cares.

I ended up getting rid of the bog by turning in that screw 1.25 turns. It ended up idling higher/highest at that setting as well. So far it appears to have fixed it. I only did it last night though.

I suggest playing around with settings on this screw. Just make sure to note exactly where you started from(screw in and count how far it has been backed out)

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