that's because everybody forgot about the 800's. Gut the box, mill the heads, advance the timing, rejet, v-force reeds, and bam you made your self a 900 for a little less if you have the know how. 1200 miles on it right from 0 miles and no problems. Lined up next to 900's and they run dead. Mine was faster on the mid and top on a few althought with proper 900 setup that would be the end of the 800.
Gutted my box on my 03 900 and love it. I haven't jetted up yet, I also am piped and still haven't needed to jet up, plugs look good. But it also hasn't got down right cold yet either. staying around 30 Degrees. Couple friends I ride with have 800's and they both gutted there box and really noticed a difference. First, take your shelf out with the cones, And then cut the wall out that the shelf clipped into the back side. You can also cut the wall out on the right side, its smaller but it still helps. People may tell you that it will hurt your HP because of air velocity but it doesn't, It helps. They say the tubes are in there to speed the air up, That may be true but I am still creating more power having it gutted. Just my 2 cents
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