1517 was a belt drive this year, mecunams normally don't use chain as BEEKMAN said, I think 126 had a belt drive in 2008, and pretty much it is not that hard to have a chainless drive.
What type of drive are you guys considering? It does sound like a neat project to use something you haven't done before, I guess that is why they call it off-season, belt, direct drive, sprockets,
other?