Purchased one of George Erl's slip on Uptite exhausts and went for my first ride over the weekend. First I'll note that I am coming off of the FMF Q4 slip on and not the stock exhaust. First thing I noticed is that the Uptite exhaust is significantly louder and has a nice throaty tone compared to the Q4. The power from the Q4 is not much different than the stock exhaust (power wise) other than dropping some weight and maybe a slight gain across the range. The Uptite exhaust is a complete change of personality. Power comes on sooner and with more authority and revs out significantly more. I was worried that with extra power I may lose of the ease of ridability that I love so much. Ridability is not lost at all, when you want/need the extra power it's just a twist of the throttle. RAting on the exhaust is 5/5. Buy one ASAP!! It also comes with a USFS spark arrestor. Quiet core is available as well if you need to have a quiet exhaust.
FMF
Low end: 3.5/5
Mid range: 4/5
Top end: 3/5
Power very smooth, almost too vanilla. Never tires you out, but not super fun or exciting.
Uptite
Low end: 4.5/5
Mid range: 5/5
Top end: 5/5
Power still very smooth, now on steroids. Brought the fun factor back!
