The exhaust system mounted with no problems and is sturdy. Sounds great. Have the same exhaust on my 400ex & son's 300ex. Buy the FMF power up kit and call FMF to help you get the right jet and your e-clip in the right place for adjustments.
The Mini Powercore 4 is the best bang-for-your-buck performance bolt-on for your mini. Offered as a standard Mini Powercore 4, Closed Course Big Bore System or as a Spark Arrestor Version, the Mini Powercore 4 features a Hi-Flo stainless steel core and formed end caps, an aircraft-grade aluminum canister and a durable stainless steel header. It's pounds lighter than stock and you will swear the motor has been bored and stroked with the first twist of the throttle.
Note: For closed course competition use only. Not intended for street use.