I am familiar with the link for the 110 Extreme engine, 3lbs.-12.8ozs is lite for a 100 twin... The previous model which was essentially the same engine weighed 4lbs.-8ozs.. On another sheet on BME's site I noted it stated the 55 would weigh in @ a sub-2lbs.

I stand by my assertion on the 55's guesstimated weight... I just can't fathom it being much lighter than the "50".