<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Concerned about that much weight that far out on the arm of the frame and also the effect of fuel economy. </div></BLOCKQUOTE>
Bob is 100% correct about weight concerns, as a lift adds so much weight to the rear axle.
Because of the cantilever effect, for example, adding 1000# lift and motorcycle will add more than 1000# to the rear axle because the weight is so far to the rear of the rear axle, it causes some transfer of weight from the front axle.
I don't think mileage would be much of an issue, whether a motorcycle is carried or towed on a trailer.
After all, it's a small price to pay to have your bike with you and ride through some beautiful country.