Well jeeze, why so harsh? I'd say Performance Upgrades is the topic but it is also pretty General. Hey, it's here now.....might as well stay. Not like everyone always posts stuff in the most appropriate forum. I might say, it has been a bit slow lately.
Some kind of tank protector is essential especially if you wear leather (which you should do - in fact safety gear is the best thing to look at buying before you get into mods). I have a Lockhart Phillips tank bra and it protects about as good as anything else could and it was cheap. ~$30. Drawback, a lot of people think it looks very Harleyesque. I like it fine though but the wedges that slide between the fairings are a hassle. A Mag Knight bra is probably your best choice for appearance and protection. It is also very easy to remove as it is just one huge refrigerator magnet that you mold perfectly to your tank with a heat gun for a hermetic seal. The Mag Knight cost about $85.
A rear stand will get used a lot at the very least for chain lubing. $60 - $250. A Pit Bull forward handle is the best and it falls right about in the middle of the price range. I would only get a front handle rear stand for the 14 unless you can count on someone to help you lift the bike every time you need to. I have a Heindl pivot stand and it lifts with similar concept to the forward handle Pit Bull but it is not as sturdy. I would still recomend the Heindl, however. It's $260.
First thing you will change is tires. There is a tire thread (and it's listed in the General Forum by bg himself!) with a poll for most popular tires.
Don't worry, you won't max the 14 out on the street so Mass is right that you might as well learn the bike stock first. That will give you an even better idea of how you want to mod. If you're going to mod, I think the Power Commander is the best thing to add first. It will improve a stock bikes performance and it will be useful for future mods that effect f/a (and most do). PCs run about $250 for the PC5. PC3 is a bit cheaper. Anyone could install a PC. It just takes a great deal of patients and some care to get those main harness plugs to come apart. I have the technique down now that I have separated them twice.
You will grow weary of the looks and sound of the stock pipes. I've ridden mine for over 12,000 miles now and they are finally starting to sound like a motorcycle. Slipons or full system is up to you. You are going to get more peak power out of a full system and drop more weight. You will extend the range at which the 14 makes power by about 1000 rpms and you will get more power than stock. It is awfully hard to hit those kind of Rs on the street. I've maxed my bike in first and I was quite well set to be sent to jail with my bike hauled away on it's side in the back of a truck if an officer was in sight. So, the question is, "how important is peak hp for your interests?" If you go with a full system plan to spend ~$900 - $15,000. Slipons $600 - $800, I think. Personally, it seemed like going with a full system was more bang for the buck when I did my research. You can have a full system for a few hundred more. I think Brock's is always a good choice if you like loud and you like racing. Part of what you pay for when you buy a Brock's pipe is his excellent maps which I hear he has a number to choose from. I plan to go with Tsukigi because I feel confident that I can get the similar performance and have it loud or quiet with the change of a baffle.
Air filter if you want. It only ads a couple of horse power and the intake increase is so slight that they don't really even have to tune for it. My research seemed to point to BMC as the brand most preferred. I got the BMC Race filter which provides maximum flow but I don't use it because it super duper thin - I mean you can see right through it. Lots of people use race filters on the street and I do not hear of probs resulting but for me personally, I won't do it in the city until the 14 is a bit older, maybe. I'd use in the countryside. In fact, I should do that this weekend. It cost me ~$80. You can get a BMC Street filter that will flow almost as good and be safer. Either way, it only gains you 1.5 - 2 hp. I think it would be a good idea to use the stock filter with the perforated steel plate removed from the underside. Some people do that instead of going after market on the filter.
A 16 tooth front sprocket will gain you some accelleration. Couple that with a 43 tooth rear and you have whole new realms of power to explore. It does not reduce your max speed by a whole lot. I have not done it because I'm sure it would be overkill for me at this point. Might go with the 16 tooth front to start because I need a new chain anyway. There is a thread on gearing (just another term for sprockets) in Performance Upgrades. I believe sprockets are about 30 - 40 bucks a piece so it's a cheap way to make a huge change in the bike.
Flies out on a G1. That's the biggest mod and there are threads about it. It's free. Flies out on a G2? I did it and I don't plan to put them in. It will not hurt a thing. About the only time the flies come into play on a G2 are at extremely low rpm so you ain't sport riding if your flies are flapping anyway.
After that you can think about NOS and light weight wheels and all kinds of stuff so be Mass's friend and see if you can weasel his secrets out! He's dropped over 100 lbs off his 14. Much better handling and braking and some more acceleration too. It gets awful expensio- if you are going to go all the way. A pipe and a PC and gearing should be more than adequate but we all can dream.
08 MIDNIGHT SAPPHIRE BLUE ZX-14 Now Deceased, will be resurected
2024 ZX-14R bran friggin NEW!
plus it seems to make the bike a whole lot lighter and well, it looks better with some nice Carbon-like exhausts under them. And yeah, the tank-protector which i always slap on any bike i ride on 
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