Let me start by copying an e-mail I sent out earlier
D&D is selling slip-ons for the 919 & Erion will have theirs ready in about 3 weeks. Better companies will take longer because they will do real R&D instead of just bending some tubing to make it fit the bike... Their is a definite science to making exhausts & contrary to popular myth not all slip-ons are created equal
Here is a dyno graph of the top two exhausts made for the RC51 ran on the same bike, same dyno same day! note the difference in torque numbers
The PCIII's for the 919 are not available yet, but I will most likely have one soon (maybe even before the general public does)
You will never get the power numbers close to that of the 900RR's... The cam phasing is tuned for low-end & midrange power as well as the throttle bodies since they are only 36mm (CBR600's are 39mm) Even if you spin the engine past the 9500rpm redline the valves aren't open long enough to get sufficient fuel mixture into the cylinder for a good burn. Horsepower is always a trade off...
I also suggest you do the flapper mod that is listed on my site www.919.org
i've already done flapper mod.it seems to work pretty well. i'm thinking of buying the erion slip ons.would it help any,and do you have to get the pc3 for the new pipes to be effective.the bike actually has enough power for my inferior skills, but a little more couldn't hurt huh!