Whats your opinions on the performance of FMF Gnarly n Fatty pipes??

I am thinking of buying an FMF pipe. I have the PC Works pipe, well, I have the stock pipe on it right now cuz I like the power delivery much better. I would like to get alot more bottom, mid, and some decent top ponies.

I appreciate the link j-bo, I looked at it right before I made this topic. I didn't look through all the pages, do they do a test on the Gnarly or Fatty pipes as well?

I haven't had a stock pipe on my bike (nor is my bike stock), but I did jump from a Fatty to a Gnarly. They are totally different creatures.

Gnarly comes on much sooner than the Fatty, much more throttle response at very low rpms. Somewhere in the middle (maybe 5-6K) the Gnarly seems to have a hit and pulls very hard, but hits a wall on the top end.

The Fatty doesn't come on as soon, but was very linear through the whole powerband. Way more over rev than the Gnarly, pulled much longer on top end.

At first I didn't care for the Gnarly, now I'm not sure I'm going to bother getting the Fatty repaired. I spend 90% of the time on single track, and grunt helps me more than revs. Plus my bike still makes more power than I can use most of the time.

I have been riding a lot of single track lately, its a loop we made (its tight). Sometimes, but not very often, I hit top speed on a fire road or open field. I'm thinkin the Fatty pipe would better suit my conditions or maybe a DEP.

On second thought, I will NEVER get another bare metal pipe again. its a shame the DEP doesn't come in plated.

I have been riding a lot of single track lately, its a loop we made (its tight). Sometimes, but not very often, I hit top speed on a fire road or open field. I'm thinkin the Fatty pipe would better suit my conditions or maybe a DEP.

I dont think the DEP would be a good choice for you. I have one, and the bottom end is quite soft, then you hit the midrange/top and the bike goes crazy fast.:thumbsup: I put the stock pipe on mine because I was having a hard time controlling it in anything but wide open spaces. Maybe after more seat time I will put it back on and use it for my track pipe.

Ever heard of black high temp spray paint ? :thumbsup:

I dont think the DEP would be a good choice for you. I have one, and the bottom end is quite soft, then you hit the midrange/top and the bike goes crazy fast.:thumbsup: I put the stock pipe on mine because I was having a hard time controlling it in anything but wide open spaces. Maybe after more seat time I will put it back on and use it for my track pipe.

Thats the same problem I had with the PC works pipe that I have, way too crazy when it hits the mid and up. I don't like the trade off, weak low end grunt.

Ever heard of black high temp spray paint ? :thumbsup:

I thought about that, for a second.

Your pipe is the stock pipe. Nothing else will really do what your asking for. My zip ty racing pipe has some potential for greatness, but so far its not there. It will take tons of work to get it to stock pipe performance.

I have the FMF factory fatty, same cones as the fatty but lighter gauge and bare metal. Can't say I notice a difference between it and the stock pipe but have yet to do a back to back comparison. They aren't that hard to keep looking fresh, less than 5 min. with a scotch brite pad and WD-40 after washing is all it takes.I prefer the look of the the bare metal pipe's especially when they blue from heat. Would be nice if they came blued like the barrel on a gun. :thumbsup:

gnarly here, pro-thicker metal = less dents. con-top end is pretty flat compared to the pc

Your pipe is the stock pipe. Nothing else will really do what your asking for. My zip ty racing pipe has some potential for greatness, but so far its not there. It will tons of work to get it to stock pipe performance.

I was wondering about that Zip-Ty pipe RCannon. Whats the story on it?

I have the FMF factory fatty, same cones as the fatty but lighter gauge and bare metal. Can't say I notice a difference between it and the stock pipe but have yet to do a back to back comparison. They aren't that hard to keep looking fresh, less than 5 min. with a scotch brite pad and WD-40 after washing is all it takes.I prefer the look of the the bare metal pipe's especially when they blue from heat. Would be nice if they came blued like the barrel on a gun. :thumbsup:

I agree that the bare metal pipes look way better than any other pipes. It wasn't very hard to clean or keep the rust off, but i have a lil OCD when it comes to things like that. I had to remove it everytime I cleaned it or it "wasn't good enough".

Gotta Gnarly here. I did too many mods and now the bike pulls too hard on the single track. It's available if you'd like it. I really didn't experience any loss in top end over rev but spend very little time there anyway. Very crisp throttle response and torquier pull.

I agree that the bare metal pipes look way better than any other pipes. It wasn't very hard to clean or keep the rust off, but i have a lil OCD when it comes to things like that. I had to remove it everytime I cleaned it or it "wasn't good enough".

I can appreciate that, but since my budget won't allow for bling I've learned to live with what my son calls the "ghetto" look. I looked at a slightly used zip ty pipe, the guy described it as "smoother", certainly RC has a better evaluation of it's performance. I deciced against it, I think the so called ceramic coating was a sales gimmick. It was thin and had worn thru in just a few rides (similar to paint) couldn't see it doing much of anything in the way of heat retention.

The Gnarly makes the top end noticeably flat. But even so, the bike still gets up to 75+ mph just fine. Just not at a "drag race" acceleration rate.

On the other hand, the Gnarly produces low end where there wasn't any before.

So if you need/want the low end and can live without accelerating from 45-70 mph as fast as possible, you'll be happy with the Gnarly.

I'm leaning towards the Fatty, I'm afraid that the Gnarly will remove more top end than I will be happy with.

You guys that went with the gnarly, did you have much trouble with jetting or did you have to re-jet at all. I read on a couple forums the gnarly was pretty much just bolt on and go????

Good question barbwire44

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