I have an '02 400EX that came with an FMF Powerbomb header and White Bros E Series S-Bend silencer. The bike runs strong, but as always I am looking for more. ATVNews.com compared 20 different setups with Curtis Sparks coming out on top.I have heard good things about his 4-stroke stuff "4-Stroke Wars Champion" and was considering his pipe or simply upgrading to the White Bros Pro-Meg silencer. Does anyone have the Sparks pipe setup? I would like to hear others opinions on this as I am new to the 400EX world! Thanks.

 

You wont gain a noticable amount of HP with this kit. Instead you will need to go into the motor. Exhausts make a dif but not much. I have had 3 diferent ones and have noticed very little if any dif. Spend that 400 on the motor. Then you will gain power.

 

With my engine, the exhaust that I have noticed the most power was from the Sparks or LRD, they are basically the same pipe. Ive tried White Bros, FMF, Pro Circuit, Sparks and LRD. Im running the LRD full system right now. It works well with my 440.

~Team440ex