Help FMF Powercore install

I bought a FMF powercore and when I went to install it the exhaust pipe is to big for the header pipe and not big enough to put the joint gasket in there.

How does the FMF clamp down on the stock header?

Did they leave something out of the box?

Thanks for your help

What sort of bike is it (the new WR?)

I bought the factory 4.1 for the new WR and didnt fit either so ive ordered the Q4 and hoping for the best

There should have been a bushing to go from stock pipe to new one

I bought a FMF powercore and when I went to install it the exhaust pipe is to big for the header pipe and not big enough to put the joint gasket in there.

How does the FMF clamp down on the stock header?

Did they leave something out of the box?

Thanks for your help

Is this the one for 299.00.

I put one on my 03 and there is no clamp, they slip in on with hi temp silicone.

I used ultra copper. does not leak.

Great pipe, works very good at mid range.

Remember the 07s have a smaller diameter head pipe to improve the low end. You must make sure the pipe is actually designed for the 07 before you buy it if you buy a slip-on with out a new head pipe.

I have a powercore4 on my o4 wr450 and there is no exhaust gasket required between the header pip and the muffler. It is a slip on fit. I use high temp silicone to ensure it is airtight and have wrapped a 1" wide strip of aluminium foil around the outside of the muffler pipe, so the clamp has plenty of bite to tighten onto.

I always thought "slip-ons" were supposed to slip on without clamps, gasket or gasket kit/silicone?:lol:

I have a powercore4 on my o4 wr450 and there is no exhaust gasket required between the header pip and the muffler. It is a slip on fit. I use high temp silicone to ensure it is airtight and have wrapped a 1" wide strip of aluminium foil around the outside of the muffler pipe, so the clamp has plenty of bite to tighten onto.

did the same execpt for the foil and clamp on my 06 and it works great. no leaks. it is a slip on

This is what I have ordered, not fitted it yet...

Powercore 4

YAM YZ250F/450F'06-07/WR250F/450F'07 P-CORE 4 MFLR

Price : $299.99

Prod # 044228

And it says it is for a WR450 2007 ??? Do I guess that the YZ has a different header pipe to the WR ??? if so may have to order the Header pipe from FMF. ..

I called FMF today and they have GREAT customer service.

He says I need the adapter (reducer) and is sending it out today UPS NO charge to me.

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