sst vs fatty

Joined
Feb 21, 2007
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#1
I'm riding a 99 yz250 and want to upgrade my expansion chamber but I'm trying to figure out which pipe to go with, a SST or Fatty. I know the website states the sst is much better but does anyone have personal expertise or have you compared the two? I mostly ride aggressive trails, cross-x tracks, and a bit of mx and I'm just looking for a bit more power....
 
Joined
Mar 25, 2007
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#2
i have heard that the sst can detonate your bike until it is tuned right.
 
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Mar 26, 2007
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#4
More than likely only on pump gas. If you only run race gas and are a pretty serious racer / biker I would go with the SST.

From what I have gathered after reading around this forum, the SST produces a stronger exhaust wave. This in turn raises the compression a bit in certain conditions.

Not everyone who has a SST have experienced detonation, but a good number of people have. If you run race gas you don't have anything to worry about. If you run pump gas its kind of a crap shoot.


If you are more of a casual rider, go with the fatty.
 
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#5
I have a 2003 RM 265 with an SST Pipe and run CAM2 110. I used to run a Fatty with this set-up.

I installed the SST pipe after riding half a day at Budds Creek. (To get a realistic side by side comparison)

I immediately noticed more pull/torque in the low to mid range. To be honest both pipes seemed very simular. But the SST's torque seemed to come on sooner and last longer into the top end. The SST has a bit more over-rev.

I am pleased with the selection. Sometimes, I lug my bike a bit like a four-stroke. While other times I rev it very high. The pipe works well with both riding styles.

As a side note, I had a cracked lower mount at the 6 months and FMF fixed it free of charge. (I had to ship it to them of course) FMF warrantees their pipes for 12 months.

If your riding woods mostly look into the FMF Gnarly. Usable power is better than having power you can't use.

Good luck, Steve.
 
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#6
I usually run 93 octane pump gas just because it's more readily available, so I guess I'll go with the fatty. I grew up racing mx, so I'm an aggressive rider, and I like to ride my bike on the pipe even when I'm in the woods, so I don't think the gnarly would be a good pipe for me. Has there been any issues with detonation with the fatty? I might have to reconsider my fuel selection :whoa:....
 
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#7
for tight trails the fatty is better sst is for higher revs.
i have a fatty right now and it is good for trails.