actually, dirtwheels did a z exhaust shootout and the hmf was quiter then the e series by 3 decibels. I also have the e series pipe(slipon) and it is almost as quiet as my stock, but thats only with 6 discs in, i plan on putting more in, but i love the pipe. Very noticable power gains, better torque, and i am really happy with the exhaust. I have also heard many good things about the hmf though, and looks to be a really good pipe.-

 

yoshmire, or hmf.





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2003 z400

 

We installed the Yoshi full carbon fiber/titanium system and jet kit on my son in-laws 2003 Z400.
The pipe sounds great; w/spark the arrester, and the power gain was very noticeable.
The complete setup seems to weigh what the stock head pipe weighs
He runs over-sized rear tires, which killed some torque, but saves rear end bashing on nasty trails.
He can now pull clutch-less second gear wheelies and gained about 2.5 mph on top end. (GPS)