KX Riders

Maintenance & Technical => KX500 Original => Topic started by: serafin on December 04, 2011, 04:41:55 PM

Title: FMF Pipe Fitment
Post by: serafin on December 04, 2011, 04:41:55 PM
Hi everyone.  Question for everyone that is running a FMF pipe. How well does it fit and mount up?  Does everything line up?  Is there any binding?  The reason I'm asking
is that I bought a Gnarly Woods (020055) and when I went to install it, it fits but things don't line up properly.  Meaning when you slide the inlet of the pipe into the exhaust port of the cylinder and attach the springs to it so that the pipe sits straight and flush into the exhaust port (new copper washer is installed) the stinger portion does not adequately line up with the opening in the sub frame where the muffler attaches to the stinger.  The lower exhaust mount on the cradle lines up as well as the mount by the rear shock lines up but the mount by the coil is way off.  The only way to make all things line up with the muffler in the subframe is to force the pipe into place which then causes the inlet of the pipe to not sit flush against the exhaust port of the cylinder.  I'm getting the feeling that this pipe when it was assembled it wasn't set in the jig correctly before they started to weld it together.  All comments are welcome.

Serafin

I'll try and get pictures later. 
Title: Re: FMF Pipe Fitment
Post by: ID KX500 on December 04, 2011, 06:25:57 PM
I think maybe it helps to remove the sub-frame so you can move the pipe more.  I finally found the sweet spot with alot of gentle persuasion.
Title: Re: FMF Pipe Fitment
Post by: 81cr450 on December 05, 2011, 01:37:16 AM
I have a steel pipe fence post I can put the stinger down in & you can persuade the pipe just a bit with it. Just be gentle about it. The mount by the coil will take a small amount of moving with a hammer as well, brass faced hammer being ideal.
Or you might want to send it back & see if you can get a better fit, I wouldnt be suprised to see you get the same thing back though.
Title: Re: FMF Pipe Fitment
Post by: Foxx4Beaver on December 05, 2011, 04:50:56 AM
Have you tried loosening all the mounts first?....I know on mine(FMF Gnarly),I find it easier to remove all three mounting bolts for the right side radiator and let it relax forward....I do this upon removal of the pipe too,only because my pipe to cylinder connection is snug,and the mount under the tank that's part of the pipe has hit my radiator before...luckily it did'nt puncture it.I would try loosening everything first and get it "relaxed"....and I agree with 81cr,you very well might get the same thing back if you exchange it for another.
I also can't gaurantee my advice is gonna work for you...just figured I'd share my procedure for removal/installation.
Foxx
Title: Re: FMF Pipe Fitment
Post by: Polar-Bus on December 06, 2011, 04:09:07 AM
Hi everyone.  Question for everyone that is running a FMF pipe. How well does it fit and mount up?  Does everything line up?  Is there any binding?  The reason I'm asking
is that I bought a Gnarly Woods (020055) and when I went to install it, it fits but things don't line up properly.  Meaning when you slide the inlet of the pipe into the exhaust port of the cylinder and attach the springs to it so that the pipe sits straight and flush into the exhaust port (new copper washer is installed) the stinger portion does not adequately line up with the opening in the sub frame where the muffler attaches to the stinger.  The lower exhaust mount on the cradle lines up as well as the mount by the rear shock lines up but the mount by the coil is way off.  The only way to make all things line up with the muffler in the subframe is to force the pipe into place which then causes the inlet of the pipe to not sit flush against the exhaust port of the cylinder.  I'm getting the feeling that this pipe when it was assembled it wasn't set in the jig correctly before they started to weld it together.  All comments are welcome.

Serafin

I'll try and get pictures later. 

Something's gotta be bent. My FMF fits perfect. A way to tell if something is not right is that the pipe will burn a spot in the underside of the fuel tank back near the seat.
Title: Re: FMF Pipe Fitment
Post by: kwakman on December 07, 2011, 03:47:57 AM
Had an 88 - 04 fmf  on my 86, and loosening all mounts to position it clear of rad was all that was needed, fitted like it was meant to be there.K.
Title: Re: FMF Pipe Fitment
Post by: NZ500 on December 10, 2011, 06:28:50 PM
I have an FMF pipe (looks like stock but plated so presume it's a gnarly, has nothing written on it). The mounts are crap and haven't been twisted or cut off. I was thinking it might have been for an earlier bike or something. I have the pipe sitting in a good spot now, looks like factory (which it didn't when bolted up with twisted mounts before) and now allows access to the power valve cover which it didn't before. I'll be changing the mounts on either the bike or pipe.

It's not getting it in place I have trouble with (I remove the muffler and it goes on fine with a bit of care), the angle of the mounts welded to the pipe are way off. Just thought I'd mention incase there's a few dud FMFs out there

Title: Re: FMF Pipe Fitment
Post by: kwakman on December 13, 2011, 02:57:55 AM
can you post a pic NZ? should be able to id it by looking, spent enuff time doing it.......AAAHHHH pipe dreams! K.
Title: Re: FMF Pipe Fitment
Post by: serafin on January 02, 2012, 02:13:56 PM
Just wanted to share the pictures of my pipe problem.  I did send it back as I just did not feel it was made correctly.

Serafin

http://s1119.photobucket.com/albums/k631/sgarciajr730/KX%20500/Pipe%20Fittment%20Problem/?albumview=slideshow
Title: Re: FMF Pipe Fitment
Post by: riproost on January 02, 2012, 05:22:54 PM
Both of my Gnarly pipes on both bikes line up similar to yours for whatever reason.
I slide the silencer on with only the bottom pipe mount on loose, then I put the other 2 mounts on and snug everything up.
When sliding the silencer on I need to give the tail of the pipe a lil tweak.
Be careful when tightening that you are not binding up the pipe at the cylinder.
Title: Re: FMF Pipe Fitment
Post by: riproost on January 02, 2012, 05:30:24 PM
What ID KX500 said---I finally found the sweet spot with alot of gentle persuasion.
Title: Re: FMF Pipe Fitment
Post by: bturton on January 08, 2012, 01:08:28 PM
I have a problem with my new FMF Desert pipe. The rear section is 3/4" too short and does not engage the silencer at all.

I talked to FMF and they said sent it back and they will double check it. Well, I'm from Canada and shipping alone would have cost darn near as much as the pipe. FMF said it sounds like the pipe was not welded properly.

When I get some time, I will just cut it open and weld in a short extension piece. Ideal solution? No way!

Sounds to me they were having welding jig issues.

Brad
Title: Re: FMF Pipe Fitment
Post by: Polar-Bus on January 09, 2012, 04:21:58 AM
I have a problem with my new FMF Desert pipe. The rear section is 3/4" too short and does not engage the silencer at all.

I talked to FMF and they said sent it back and they will double check it. Well, I'm from Canada and shipping alone would have cost darn near as much as the pipe. FMF said it sounds like the pipe was not welded properly.

When I get some time, I will just cut it open and weld in a short extension piece. Ideal solution? No way!

Sounds to me they were having welding jig issues.

Brad

It's so odd you guys are having fitment issues. You would have thought that FMF would have the KX500 pipe fitting sweet as FMF has had 23 years to fine tune their jig. Maybe some 11 year old malaysian child worker grabbed the CR500 jig instead ?   :-D
Title: Re: FMF Pipe Fitment
Post by: lifeishp on January 12, 2012, 07:49:03 PM
i made my own fmf fatty for my bike because they don't make pipes for my year. modified an 87 pipe to fit my 84 hillclimber. little welding here, little welding there, fits great and runs stronger. more of a hit, it actually idles somewhat now and it revs higher. i also used a fence post extender but that was to lengthen the pipe. it was the only thing i could find and it sort've looks good with all the rest of the chrome pipe.