Old FMF mid top pipes compared to Fattys

[rubeat]

I have a old set of fmf mid top pipes on my shee and I thought maybe a set of fmf fattys would be better. So i tried a set and they killed my shee.I rejetted and changed pilots when i switched.They made my bike totally lazy, slow reving to the old pipes.I was shocked it sucked in the whole powerband with the fattys. I was thinking about trying a set of t5s but dont want to spend the money if they wont help. Has anyone else done back to back tests before with these pipes? I put my old fmfs back on and the power is back so i dont think anything else is wrong. Thanks Mike

[AKheathen]

sounds like the jetting was still off. what other mods did you have? reeds/porting/timing?

[rubeat]

I have no porting, +4 timing, and carbon fiber reeds on stock cages.I'm about 400 ft above sea level and was jetted at 320 mains and 27.5 pilots with stock carbs and k&n pods.I thought my jetting was perfect I could be wrong.But the thing was a turd with the fattys on it. I put my old pipes back on and never changed the jetting or anything and the power was right back.It just started a little harder until i changed the pilots back to 25s and jetted back up to 340 on the mains. Maybe im missing something else i hope not because i sold them already. Are the old mid top pipes that good of a pipe? Thanks Mike