View source for Why performance mods might not be good for you

[[Category:Engine]]
Posts asking about performance mods come in a dozen times a month, quite often from one-post-wonders who get a bike and want to put on an aftermarket exhaust, remove the airbox, and/or mount wider tires before they even learn how to ride it. These kinds of people generally ignore any advice, no matter how experienced the author, unless it agrees with what they want to hear. We're going to try anyway.

If you've been riding for a while and have a clear idea of how you can make your 250 do more, you can ignore this article. 

It is the general feeling of most members of this club that if you're looking for more power, you're on the wrong bike. That said, here's what you can do: How much HP do you want? 

*1-5 : Exhaust pipe, intake and jet kit 
*3-8 : Porting, compression increase, cams 
*20+ : trade the Ninja 250 for a bigger bike. 

The most economical of these is the trade. You can get a good used 600 or a superbike in fair condition for the price of a new 250. 

If what you really want is to be able to go faster, then learn to ride better.

'''Here are some member opinions on the matter. YOMV.'''

*Don't screw with the bike, just ride it. No one CARES what it looks like other than you. And if you remove the airbox (or really, try to do any "performance" mods, like changing the exhaust) prepare to spend 80% of your time working on the jetting and 20% riding it and wishing it worked better. You'll eventually either give up (70% likely) see the light and go back to stock (20% likely) take it to a competent shop to let them fix it (9% likely) or get it right on your own (1% likely).

*The Ninja 250 is never going to be a powerful bike. The cost for the extra HP on the Ninja is pretty high for what you get. If all you want is a few more hp, then go ahead. 

:It is important to note that the addition of a pipe/K&N pods/jet kit, etc… does not increase the selling price of a Ninja, and may in fact decrease it. Many people look for a stock bike when they buy used. 

:If you want much more hp, the cheapest way to get it is with a 600. The old ones are a dime a dozen and are fairly reliable, and even somewhat comfortable.

*Here's the bottom line: Each horsepower is going to cost you about $100. Let's compare:

:Used 250: $2500. Sure, older ones are cheaper, but they also need more basic maintenance items to bring them up to spec.

:$500 for another 5 HP = $3000. 38 rwhp (maybe) for $3K. 

:Used 600: $4000. Let's say this one: 3-5 year old Kawasaki ZZR600. 98 HP for $4k. 

:Now, if you're after max HP, why buy a 250?

*Making changes for "power" slides the bike's usefulness from "all around" to "focused", as well as causing it to need a bit of expensive tuning work to function correctly. Riders new to the world of motorcycling don't generally have the experience to do it themselves, nor do they think about what they're giving up for what is, ultimately, a cosmetic/ego mod.

:If  people would just RIDE their perfectly functional, needs-nothing-except-wear-items bike, they could become Riders instead of Posers.

*It's nearly always a bad idea to try to turn a bike into something it's not, and that's because:

:- the result almost never matches expectations.
:- on resale, recovery on the mods is lousy. It can even be negative. Stock bikes always attract the largest number of potential buyers. Performance-type mods can make the buyer assume you're a squid and you stunted it.
:- dissatisfaction is a feeling you should not usually allow to creep over you until you've owned a bike for a while. Then, if there's a good reason to feel that way (not pressure from your buddies, or from marketing hype) the appropriate remedy is usually a different bike.

*If you want to futz with a bike, do it on a second hobby bike, and leave your main ride alone. That would be the best of both worlds.

*There's no engine/intake/exhaust "free HP". You basically rob Peter to pay Paul... meaning that if you want more HP (a peak number achieved at high rpms) you lose low-end torque and HP to get there. If you want more low-end grunt, you're going to lose top-end HP. The only "free HP" is losing weight, either from the bike or the rider. 

*There's a balance to the EX that I like, and as you up the power you make the bike less balanced, more highly-strung, narrow down the power band and, unless you're willing to spend big bucks, increase the possibility of engine failures, along with mucking up driveability.

*You have to realize that "power" does not come from the engine like water from the tap: open the hole wider & you get more water. 

:First of all, when you change your carburetor's jetting, you alter the engine's performance for a specific range of rpm. For example, changing a jet needle will have very little effect on low throttle and WOT performance. Those additional horses that you're talking about will not suddenly appear over the entire range from idle to wide open throttle. You have to know where you want the additional power. 

:Second, you need to be an experienced mechanic with either a very good feel for the bike or specific equipment (such as a dynamometer or a set of sensors to gauge the fuel-to-air ratio). The typical novice rider is rarely an expert mechanic. He is much more likely to completely screw up his jetting than to obtain ANY extra horsepower at all. In short, besides knowing where you want the additional power, you have to know how to get it. 

:Those are the reasons why we tell people to leave the bike alone. By the time you're ready to mess with jetting, you will know so much stuff that you will not be asking questions here in the first place.

*If you like to have more power (even a small bit) want to have more than one bike, and want the most out of your little Ninjette, then there is nothing wrong with some tinkering. There are much easier ways to do so, though.