Originally Posted by Headpost

Thanks to everyone for the compliments, advice, ideas. I'm still not sure what I'm going to do, but someone at Co-Motion was nice enough to get back to me so I thought I'd share their (edited) response:

Thanks for your inquiry- you’ve got yourself a very unique frame there. We made two such bikes, and “mule” was not a model name, the name was painted there by request. It was an idea a customer had for a bike that he thought of as an all purpose, pack-mule like animal. He wanted to ensure that it would fit the largest 700c tires he could find, and so we built him a frame that would do just that. Months later, he found still larger 700c tires, and talked us into building him a frame with even more tire clearance. As a result there are two of them, both featuring the Mule name on the top tube, both painted the same frog green color.

I believe these frames were built around 1990 and were sold as framesets, so the complete build was done by the original owner, however certainly Mavic rims, Deore hubs and 6 speed drivetrain would have been the norm for that time. As I recall the build had cantilever brakes and drop bars, probably with bar end (barcon) shifters.