I recently purchased an 88 wing with california sidecar and have gotten terrible gas milage. 11-12 mpg highway. Spoke with 2 others who own a 92 and 90, they tow a small trailer with theirs, and experience similar fuel consumption. I had a 86 aspencade in 92 with a hannigan sidecar and had gotten 35 mpg highway. I am disappointed in this machines milage but love the style and performance. Is there a way to improve fuel economy?