Viper Gas Mileage (Pipes)
I have the same sled w/ CPR pipes. Great sled, pipes could use a little better fit & finish but I cleared that up in an afternoon w/ my welder and some creativity. As far as mileage, I typically see between 9 & 12 depending on how I'm riding. Reliability has been good - I have 5100 miles on the sled, about 2800 this season with a Tempaflow and I love it. I ride in International Falls, MN so I see the same range of temps you described. This year I rode with the same jetting from -30F to +50F and my EGTs were consistent at all times. I can't comment on which pipes are best but if you do some research on here you can probably make a good decision. I would highly recommend a Tempaflow or similar compensating device to avoid the jetting changes you describe. I'm going to add remote fuel screw adjusters this summer to help dial in the low end and hope to get my mileage up in the 12 - 13 mpg range consistently.