FMF Gnarly vs. Fatty

Joined
Jan 26, 2004
Messages
8
Likes
0
#1
Hey, I just bought a 2000 KDX 200 and i love it! But in the near future i would like to order a pipe. i have rounded it down to the FMF fatty or the gnarly. i have noticed in these forums that alot of people like the gnarly pipe for the 200's. But on the fmf website they show that they fatty has more all around power? BTW if it matters I am 14 5'9 135 pounds. The type of riding i do is drag racing my friends and trail riding.
IF i dont get a pipe but only get a silencer.. will a fmf shorty silencer help any on a stock combustion chamber?

any info. will be helpful thank you
 
Joined
Sep 30, 2002
Messages
23
Likes
0
#2
Your best improvement will be a pipe. If you do alot of trail riding, then go with the Gnarly. If all your gonna do is drag race then go with the Fatty. Both pipes are good. The Gnarly is thicker and can take more punishment from trail riding than the Fatty can. I had a 96 KDX 200 that I put a Gnarly on and I couldn't believe the difference. I would blow away the 125's from the start, and in the woods, but on the straights they'd catch me. Luckily, there isn't that many straight aways in the woods.

You have to remember that 200's are woods bikes, not MX bikes. For overall performance I think you would be happier with the Gnarly pipe and a FMF Silencer. (Get rid of the stock silencer!)
 

wibby

Mod Ban
Joined
Mar 15, 2003
Messages
997
Likes
0
#3
The Fatty only fits 200's from '86-'88 and '89-'94

For the '95-present they have the Gnarly Woods (torque) and the Gnarly Desert (rev)


*******
You may have a Fatty on your H model, but they don't have 'em anymore at FMF
 
Last edited:

KDXNick

Subscriber
Joined
Oct 15, 2002
Messages
53
Likes
0
#4
I've tried both (Gnarly Rev and Tourque) on my 99' 200. I like the rev pipe b/c it encourages a faster, more aggressive riding style. The tourque pipe allows the rider to be a bit lazy, as it does'nt require carefull clutch/throttle control. With my suspension mods, I smoke my friends in the woods (one rides a KTM 250 EXC), and always pull good finishes in my HS races. A silencer wouln't help much at all. If you read any reviews on KDX mods, you will know that your money will be betterspent on a pipe, intake, or tires. Dirt Rider magazine stated: "If it ain't broke don't fix it", when refering to their decison not to replace the stock silencer on their project KDX. If you want to beat your friends on the trails or in the woods, get a pipe for your KDX. If you want to win drag races with a dirtbike, buy a MX bike, just save a little money for clutches and top ends if you plan to trail ride alot.
-Nick
 
Joined
Jan 16, 2004
Messages
14
Likes
0
#5
I'm confussed

wibby said:
The Fatty only fits 200's from '86-'88 and '89-'94

For the '95-present they have the Gnarly Woods (torque) and the Gnarly Desert (rev)
I just bought a '98 KDX 200 that has an FMF Gold Series Fatty pipe. How can this be. :ugg:
It doesn't appear to have been modified in any way.
I sure wish it was a Gnarly though... :think:
 
Joined
May 17, 2003
Messages
549
Likes
0
#7
I bought a '95 200 with a Fatty pipe on it. It is the same profile as the newer -30 (rev) gnarly only with a lighter gage steel. I later bought a gnarly -35 (woods) pipe and prefer it to the rev pipe. The -35 pipe is slightly stronger in the bottom and slightly softer on top than the -30 pipe, but without the "hit" in the midrange. I expected a bigger difference between the two pipes than there was. The -30 with the FRP torque ring actually would not pull as high of RPMs as the -35 w/o the ring. I tested this combination against an XR250 in a drag race to see these results. The -30 pipe encourages you to ride the bike more like a 125. Apparently FMF dumped the Fatty designation on the rev pipe a few years ago and went with 18 gage steel and the gnarly designation. The -35 needs 1 or 2 sizes leaner on the main jet than the -30 (if memory serves).
 
Joined
Jan 16, 2004
Messages
14
Likes
0
#8
I did buy a torque ring for the Fatty, but haven't put it on yet.
I am mostly concerned with lower end power, as most of my needs are for tight woods. When racing I'm lucky to hit 4th which would only be for short open areas...not a big concern for me.
I guess I may be looking to swap out my Fatty for a Gnarly soon :aj:
 
Joined
May 17, 2003
Messages
549
Likes
0
#9
With the torque ring the power characteristics of the -30 pipe didn't change at all. It all just happened 200 to 300 RPMs lower. I went from being walked away from (-30 with ring) in a drag race with an XR250 (top speed in 6th gear) to walking away from the XR250 (-35 no ring). All that with a slightly stronger bottom end and no midrange hit (with -35). The biggest change with the ring is the sound: It sounds more like a 250 than a 200. Remember, both the rev (-30) and the woods (-35) pipes are called "Gnarly" now. Be sure to get the one you're looking to buy.
 

canyncarvr

Subscriber
Joined
Oct 14, 1999
Messages
4,005
Likes
0
#10
I've seen 'H' model kdxs with fattys, too. Says 'fatty' right on it.

Still, by the catalog, the fatty is not spec'd for the 'H' kdx.

I've not tried to fit one on an 'H' model. Maybe they bolt right up! (well, as well as ANY FmF pipe does!)

The fatty was fabricated from 19ga. The -30 (rev) and -35 (torque) gnarly series pipes are 18ga.

I have a k-30 that is a 19ga. rev profile. It doesn't say 'gnarly' on it.

I'd like to hear of an 'H' owner that bolted on a fatty.

...or a PC-II, for that matter.
 
Last edited:
Joined
May 17, 2003
Messages
549
Likes
0
#11
CC,
My '95 KDX200 is definately an 'H' model. Pipe reads "Gold Series, FMF, So. Calif., Fatty". Also has "K-30" on one of the mounting tabs. Fits perfectly.
 

canyncarvr

Subscriber
Joined
Oct 14, 1999
Messages
4,005
Likes
0
#12
The profile # of the fatty was not '-30'. :think:

What you have (I presume) is one of the many differently named pieces that FmF produced..'fatty' being one of 'em.

If it's a -30, though...it's likely a rev profile.

That's part of the problem with FmF...them saying woods/desert/gnarly/burly/fatty/etc/etc....

..is misleading.
 
Joined
Dec 29, 2002
Messages
441
Likes
0
#13
Rhodester said:
I tested this combination against an XR250 in a drag race to see these results.
How'd you do? I used to ride a '96 XR250 and now ride a '96 KDX200. Dunno how they'd do in a drag, but the KDX handles worlds better than the mini-diesel pig, IMHO.
 
Joined
Jan 16, 2004
Messages
14
Likes
0
#14
So does anyone know if a Fatty (rev) pipe for a '98 KDX 200 would fit a '00 KDX 220?
If so, from what I have read here in this thread, the rev pipe for the 200 will respond more like torque pipe for the 220? :clue:
 
Joined
Dec 20, 2003
Messages
23
Likes
0
#15
NM_KDX200 said:
How'd you do? I used to ride a '96 XR250 and now ride a '96 KDX200. Dunno how they'd do in a drag, but the KDX handles worlds better than the mini-diesel pig, IMHO.
I just bought a KDX220 "04" and have been cruising this site and loving it.... But I can not figure out for the life of me what IMHO or IMO means..... I hate to sound stupid but could you "splain" it to me.....
Thanks,
Randy