Tslepebull
Active member
Look at my post big 1st day. I had 2 fuel runs on it, although my machine still has less than 1000 miles on it
Yes exactly, it was your report that got me thinking about this again. Many of us have been reporting mileage around 30 (presumably, 87 Octane fuel). When you filled up with 90 octane non-alcohol your mileage looked more like that BRP had predicted to me. I will be filling up with mid-grade (89) next time to conduct my own test. If the knock sensor is sensitive enough retard timing significantly it might explain the lower mileages reported by myself and others. On the other hand it might be a fueling issue related to the computer; my understanding is that the ACE 900 engine has not passed the California CARB clearance yet. I don't think BRP was blowing smoke when they gave MPG estimates (post 41) but we are not empirically getting the same results they predicted. The owners manual says that 87 Octane is approved but premium is "recommended" maybe it really makes a difference.
I am in no way bashing BRP here; if something as simple as fuel grade makes a significant difference it would be great for all of us to know. I really like my Rally I just want it to reach its full design potential.