FMF PowerCore need suggestions

[Matty05]

Ok thanks for the info. I was reading the instructions and the instructions said something about making sure all bolts and CLAMPS were tight and the only clamp was the OEM one I removed with the stock pipe. So that kinda confused me. ?

Probably generic instructions. ?

Some of their pipes have straps or clamps to hold the muffler at the rear bolt hole.

[CALVIN_KLEIN88]

How much of a re-jet did you guys need when you went to the aftermarket exhaust systems? I'm getting ready to upgrade too and am curiouse what all is needed.

[YamahaWR450FMike]

I haven't had a chance to ride my WR450 with the new Powercore yet. Just started it up and it sounds very nice. I will report back with my experiance with the new pipe at the end of this weekend.

[Terrain Rider 4z]

I use the clamp on my PowerCore and everything is fine.

If you ride off road do not remove the spark arrestor. All we need is bad press from someone running around without a spark arrestor when a forest fire starts. This does happen!

[Rip Wheeler]

How much of a re-jet did you guys need when you went to the aftermarket exhaust systems? I'm getting ready to upgrade too and am curiouse what all is needed.

I did do the JD kit, but not because of the new pipe, just wanted to upgrade. Never ran the PC4 witht he stock jetting. Oh, get the extended fuel screw also.

[Rip Wheeler]

Probably generic instructions. ?

Some of their pipes have straps or clamps to hold the muffler at the rear bolt hole.

Yes, mine had the strap with a rubber insulator. Much better than the tab that breaks off with vibration.

[Matty05]

Yes, mine had the strap with a rubber insulator. Much better than the tab that breaks off with vibration.

I have read a few times and even in mags that the strap is what breaks? ?

[Matty05]

How much of a re-jet did you guys need when you went to the aftermarket exhaust systems? I'm getting ready to upgrade too and am curiouse what all is needed.

I had to spend a fair bit of time rejetting my bike, but you will learn what everything does in one day.

Just change one thing at a time untill you can really diagnose what is going on.

The more free flowing the pipe, the more sensative jetting becomes.

What model you got???

If you have an '05+ Get a GYTR AIS block off kit to start with, it comes with adjustable needle and the 48 pilot jet you need. Then get an adjustable fuel screw at the SAME TIME. It is invaluable. Get 168 and 170 main jets, as 165 is stock.

The ultimate jetting kit:

http://www.ziptyracing.com/products/product_detail.aspx?id=MTEwOA==

[CALVIN_KLEIN88]

Right on. I have all the usual mods done and already jetted in that ball park. The yosh guy said all I would have to do is bump up one size on the main but that sounded too easy... Appreciate the info.