pic: Team 870 Front Drive Train
 

Any reason why you choose a chain drive over gears? Generally gears would've given a smaller weight and a much smaller chance of failure.

we're using gear reduction this year actually. all together there are 3 nylon gears in the drive train (saved a lot on weight thanks to the nylon).

are those sprockets made of nylon? what exactly did u make out of nylon?

the sprockets themselves are made out of nylon