the jet is a part of the carb that tells it how much gas to add to the air. My advice: dont change the carb yet, as the others said. Wait until it's done breaking in, find where the weaknesses are. I wouldnt go with that pipe either, I've heard more bad reviews than good. the SBP has the most good reviews I've heard. You, being in Canada, are going to get charged an arm an a leg for shipping anywhere but speeddemon. Avoid the banana expansion pipe too. Do you have fabrication skills and tools? Welding and dremel experience are huge pluses in these motors. A lathe, pipe bender, and perhaps a mill (if you go extreme) will be assets, but not required, a lot can be done by hand to boost the power substantially. I actually have a checklist I like to give new modders:
#1: Determine what speed you want to go - set a goal, 80kph is basically the fastest anyone's ever been on these bikes (that I'm aware of). I'm aiming for 100kph as an end-goal but right now I'm shooting for 80 for safe-ish highway travels
#2: What loads are you planning for? - If you're a heavy dude (say, 250+), plan on hauling alot (maybe you have a bike trailer or a child carrier?), or have to deal with alot of hills, you'll want low end torque and may have to sacrifice top speed, depending on where you want that to be (50kph is commonly though to be the maximum safe speed, beyond that is 'scary', though I constantly rip around at 60, aiming for 80).
#3: Determine your gearing - Your top speed may result in different gearing, it's inadvisable to push these motors past 8500 RPM (about 71kph on a 36T, or 58kph on a 44T) This may also determine if you have to pedal to help it go from a stop. (this is null if you opt for a shift-kit, but I dont like them, if the motor produces too much power it can destroy the derailleur, not to mention adding parts to fail is never a good idea IMO)
#4: Are you aiming for long range or speed? - Obviously this will affect your milage, at 60kph I get around 80mpg, though others have achieved close to 145mpg, but at around 25kph.
All of these are comprimises through which you'll have to decide where you want to be, #4 will be set marginally by your carb jet, however it can affect the first 3. For example, running lean may net you more power and gas milage, but you may end up running dangerously hot.