FMF exhaust install issues

smotalchaos

New Member
Mar 10, 2008
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I ordered a new FMF fatty and powercore 2 from a company on ebay. When going to install it today i ran into a few problems:

The pipe comes with a slip joint between the pipe and new flange that bolts to the cylinder head. There is a loop to hook the spring to on the pipe, but not on the flange. Also no where on the cylinder head.

blasterexhaust004.jpg


I know I could weld a washer to the flange but should it not come ready to go from FMF? Also shouldnt there be a new gasket for between the flange and cylinder head?

Now, I know i could forget about the spring altogether and rely on the high temp silicone and top mounting bolt to hold it in place, as some members said they have dont here, so i test fitted the pipe. The top mounting hole on the pipe does not line up with the hole on the frame:

blasterexhaust001.jpg


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I could force it to line up, but I dont want it to leak. Are all FMF pipes like this? Is it possible they shipped me the wrong one?

I dont understand why they dont make the mounting flange like the factory one without springs.

blasterexhaust005.jpg
 
on my old fmf there was a little tab welded on to the manifold so i could hook the spring to that, there should be a gasket between the manifold and the cyli, the top mount for the pipe you can move that down so it will line up, you can run the quad with out the spring you just you just gotta make sure the pipe is nice and tight, i have ran my quad with out a spring on the pipe and it held up fine..
 
i saw take it to a local shop marked were the spring lines up and have them weld a loop on the flange. the shop im at has just a box of these little pipe spring loops and they just weld them to anything. if your lucky they could just do that for you but high temp silicone works.

about not lining up, your probably going to have to bend the pipe slightly and just get it to fit. it will, my pipe took some bending work. not alot just tweaking it slightly to line up. and that top mount is on rubber so it doesnt have to be perfectly lined up because it is bolted to the top so you can spin and if you have to, twist it abit.

fmf or who you bought it from cant really do anything. if you want a flange with the spring loop, its like 30 bucks from fmf or something.
 
The spring hooks to the cylinder head, it hooks between the cooling fins, just look you will see it, and the bolt hole is rubber mounted it will flex to line up . Don't forget to jet it before riding
 
ok i see where i can hook the spring to the fin....and i didnt notice that the top mount was rubber mounted....ill use high temp silicone between the cylinder head and flange, and also liberally in the slip joint....still dont know why they make it like this though lol.....

thanks everyone that was fast!


is it necessary to jet it with this exhaust? i was planning on doing it but not until a later date.
 
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Move the needle to the center position and put a 270 main jet and remove the airbox intake tube -as per fmfs web site-
 
You will be on the lean side with the new pipe and if you do ne thing to the airbox ie.remove the lid, k&n filter you will be real lean. lean will seize your motor.