ADD a Little Low end

Hey I just bought a 2008 yz 250f and It seems to have a lack of low end in comparison to my 02 with an FMF pipe. Is there anything I can do to get a little low end grunt.

I had the same problem,i piped it,twin air and jetted now i like where my torque is!!

If you get an exhaust system you can move the power down lower but it will take away from the top. It's the dimensions of the header that'll change the power curve a bit

If you get an exhaust system you can move the power down lower but it will take away from the top. It's the dimensions of the header that'll change the power curve a bit

Hey Swede, How does one know where an exhaust is going to move the power?

What William was saying in the other thread a longer narrower one is going to move power to the lower end where a shorter fatter one is going to move the power higher

What William was saying in the other thread a longer narrower one is going to move power to the lower end where a shorter fatter one is going to move the power higher

That makes sense to me. While I'm no engine expert, I'd imagine there should be a certain amount of backpressure for the engine to have the best combustion. With the narrower pipe, the pressure will be higher (right amount of pressure) on the low end, but too high at high RPM. On the other hand, a fatter pipe will have too low pressure at low RPM but the right pressure at higher RPM. Something to do with fluid dynamics... Or maybe not, but it might be what's happening:bonk:

One very common misconception people have is that they think that 'hit' they feel is a sign of real power when in reality, it is often a sign of a poorly setup engine. The fastest bikes (and cars) are ones where the power is very linear. People put on a pipe (typically) and it takes power from one area and adds it to another. They feel the sudden rush of power and are convinced the bike is faster. Thing is, the bike is slower until the power 'hit' occurs.

Linear power makes for easier riding. An easier ride makes for a faster racer. They only way to accurately compare is to time the bike with an expert rider.

So if a pipe is pointless ,,what are my options?

Cams and/or big bore is the hot ticket.

I notice more low end power with a mega bomb but it's already jetted for that, has hotcams, and a ported head.

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