Make my 07 perform like my 04.

[Lennie]

I just bought a new 07 wr450 to replace my 04 wr450. The 04 has had all the free mods done, yzf pipe with fmf powerbomb front pipe, adjustable fuel screw and a jd jet kit. My 07 has the same stuff along with the ais removed but it has a performance insert in the standard exhaust and a yz front pipe. It doesnt feel quite as good, the power is still there but it doesnt have the kick of power my 04 had.

What other bits can i do to give it more power and feel more like the 04? Is it the exhaust thats is making the difference?

[CanadianWR450]

I believe the 04 was the last year before they "mellowed out" the power hit with lower compression, different heads and cams.....

I've seen several threads on here on the subject

[ww44wrf450f]

Agree on the melowed head, If you have already replaced the header put a DR.D slip-on, and a Hot-Cam exhaust cam would be the best bang for the buck other than that it would be some port,polish,headwork,hc piston, vortex ignition and try to take some weight off the bike or yourself lol! Some fellow ttr's have discused batteries that will shave about 4lbs? I asume that you have done your suspension already?

[Lennie]

I think a proper end can would be the next thing. I wont be taking the engine apart for pistons etc.

[CanadianWR450]

I think a proper end can would be the next thing. I wont be taking the engine apart for pistons etc.

I agree, the pipe would be your best bet, and a exhaust cam would be the thing to get the "hit" your talking about if your still unhappy after the pipe. My point was simply that the ones since the 04's just don't "hit" like the 03/04's did, and that is on purpose, and by design. Same power, just different delivery, better for woods/trail riding, and more tractability.

The YZ or Hotcams exhaust cam would be the thing to make it more MX'ish with the power hit.

I have a 04, with Hotcam's, FMF and JD Jetting, etc, and I LOVE the "hit", but I only ride for fun and grins. I know guys that do harescrambles and stuff, and they hate the power delivery of my bike for anything like that, but even they admit it sure makes it a fun play bike...