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02 CR250, FMF Fatty vs Gnarly?

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Wanting a more progressive torque curve, more traction, more low - mid range power.  Not sure which ones of these pipes is better.  I was told the FMF Fatty was the way to go, but reading up on the Gnarly makes me think perhaps its the gnarly? 

Anyone actually have experience with both? 

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What type of riding are you going to be doing. The gnarly is by far the best for the woods and gives the bike a lot of power down low but it signs off early.

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Off road, little to no track riding.  I don't mind flying through the air and all, but the last time I did that stuff I was 23 years old and I destroyed my ACL.  Post surgery 3 years afterward, fast forward to my out of shape married father body, and I'm not that into the idea of corning tight to grab power down low to clear a big gap.  

Mostly off road.  I've got a lot of technical rocky stuff, and some wide open 5th gear trails right behind my house.  Primary motivation for the pipe is more usable power range, and better traction / low end power.

I had a 4 stroke that did this for me, but I can't stand the maintenance on a those bikes.  Not a fan at all of messing with intake/exhaust valve gaps and timing etc.  I went back to 2 strokes purely for maintenance and weight.  But they really do lack the smoother progressive power range of the thumpers.  I'm hoping a pipe will help this. 

Edited by Munition
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11 minutes ago, ScrewMx_Hd said:

pretty sure gnarly is thicker gauge too if you're worried about protection

There is the advantage.  .   Living through quite a few of them (my son still has a 2000 we got in early 2001).   None of the pipes gives a big advantage with better low to midrange.  Far more useful and  lots cheaper is Boyesen dual stage reeds run with a stock or procircuit pipe.  next up is going to be flywheel weight.  Everyone I know who has tried a Keihin pwk carburetor liked them better than the mikuni which came on the 02

Edited by ossagp
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Off road, little to no track riding.  I don't mind flying through the air and all, but the last time I did that stuff I was 23 years old and I destroyed my ACL.  Post surgery 3 years afterward, fast forward to my out of shape married father body, and I'm not that into the idea of corning tight to grab power down low to clear a big gap.  
Mostly off road.  I've got a lot of technical rocky stuff, and some wide open 5th gear trails right behind my house.  Primary motivation for the pipe is more usable power range, and better traction / low end power.
I had a 4 stroke that did this for me, but I can't stand the maintenance on a those bikes.  Not a fan at all of messing with intake/exhaust valve gaps and timing etc.  I went back to 2 strokes purely for maintenance and weight.  But they really do lack the smoother progressive power range of the thumpers.  I'm hoping a pipe will help this. 

11 OZ flywheel weight then, skip a pipe
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If you are set on a new pipe go with the gnarley over the fatty. If your stock pipe is in good shape mill your head to set your squish, put on a flywheel weight drop a tooth on the countershaft and that should still leave almost enough to buy a new tire while spending the same amount as you would on a new pipe.

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Its an 04 CR250r by the way.  

Front sprocket is a 13 tooth which I could easily adjust.  Not sure what the stock fly wheel weight is, but I'm generally not a fan of how drastic changes in the weight affects a bike.  Not looking to build a bike specifically for one type of riding.  Something in the middle should be ideal for wide open stuff, and technical tight single track riding.  I would imagine my stock fly wheel is fine for this no?

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I had the Gnarly on a KTM 200 and now I have the fatty on the CR 250, I went with the fatty on the CR 250 because there were a few occasions that I wanted a little more on top with the gnarly (on trail rides it was connecting roads or long straight aways). I don't consider myself a fast rider at all, so the thought of maxing out the top end with my limited skill left me less than excited about the gnarly.  Gnarly is definitely thicker and stronger, but I add a pipe guard to almost all two strokes I have owned since I only ride trails.

 

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3 hours ago, Munition said:

Its an 04 CR250r by the way.  

Front sprocket is a 13 tooth which I could easily adjust.  Not sure what the stock fly wheel weight is, but I'm generally not a fan of how drastic changes in the weight affects a bike.  Not looking to build a bike specifically for one type of riding.  Something in the middle should be ideal for wide open stuff, and technical tight single track riding.  I would imagine my stock fly wheel is fine for this no?

Not if you are considering the smooth and linear powerband that you suggest.  Drastic is not what I would call the stealhy type bolt on weights.   Your current flywheel rotor is not be changed,  just an added (and removable) flywheel weight is added.  Removes quite quickly in fact.   The head work will give some low end snap,  but it can increase the hit.  On the earlier rigs,  setting the squish by turning the bottom of the cylinder will yield a more slick surface friendly power band.  again, you can get that back with a thicker base gasket if you don't like it.  very inexpensive,  and since you wont be changing the shape of the combustion chamber,  any machine shop that wants to,  can do it.  

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35 minutes ago, timbanditos said:

I had the Gnarly on a KTM 200 and now I have the fatty on the CR 250, I went with the fatty on the CR 250 because there were a few occasions that I wanted a little more on top with the gnarly (on trail rides it was connecting roads or long straight aways). I don't consider myself a fast rider at all, so the thought of maxing out the top end with my limited skill left me less than excited about the gnarly.  Gnarly is definitely thicker and stronger, but I add a pipe guard to almost all two strokes I have owned since I only ride trails.

 

Your 99 has the best cylinder I have found for cross country work of any kind.  takes over boring better than any of them too.  

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I have a 2001 CR250 and I run a Gnarly pipe and the stock pipe.    I run the the Gnarly pipe for off road and some of the MX tracks I ride that are on a hill or with short straights.

Get the Gnarly pipe.  It is nice to have for climbing hills, off road and for certain MX tracks.   If you don't need the Gnarly for certain riding switch to the stock pipe.

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