I have a 2000 kdx 220 and I bought my pipe off e-bay its a fmf gold burly pipe. but i can only find a gnarly pipe on fmf's site. I bought a new fmf silencer and i removed the snorkle on my air box. my question is what kind of pipe is this rev or tork?
When FMF originally introduced their line of pipes with thicker gauge material they were called the "Gnarly" pipe. They later discovered that "Gnarly" was already trademarked and were forced to change the name to "Burly". The FMF Fatty, Gnarly and Burly pipes for KDXs all use the same two profiles. If you look under the vertical mounting tab (near the top of the kick start lever) you'll see either a K_-30, a rev pipe, or K_-35, a torque pipe.
"hit like a KX250" The rev pipe will certainly give the 220 considerably stronger power delivery over the stock pipe and yes there could well be a strong hit through the mid range. The thing to remember is that you can alter how your bike makes power depending on how you choose to tune your carb/jetting. For example a C taper needle will offer a stronger mid range hit than a B taper needle because its leaner through mid throttle settings. A stronger hit doesn't necessarily mean more power but rather how power is delivered. My KDX220 has a more abrupt hit than my YZ275 but does it have more power, not a chance. The KDX is tuned for a stronger hit because I ride in power robbing loose sand. I can take advantage of the 220's good bottom end grunt and lug the engine in the tighter stuff then when things open up the stronger hit gives me the trust I like when things open up.
I like that type of power delivery from the KDX, it suits my riding style and conditions. Would I like the same power delivery from the YZ? No way it wouldn't be to my advantage at all. The point is to take your time and find a combination that works right for you and remember a strong hit has nothing to do with how much power the engine is making but rather how the power is being delivered.
The stock spark arrester is actually a decent performer for most people and is really quite. However its also really heavy. Swapping to an aftermarket silencer shaves some weight and increases power slightly.