Originally Posted by
juntjoo
What are you saying about this "sync" chain? I haven't measured mine. As far as I've learned, just recently learning about bikes, is single speed should be 1/8" gauge/thick
Most tandem bikes have two separate chains, one of which goes to the rear wheel from the second rider's crank and the other goes from the front rider's crank back to the second rider's crank - this is the sync chain and it does not do any shifting. On our tandem, the rear chain is a nine speed because we have a nine speed cassette. We also use nine speed chain for the front sync chain, even though it could be thought of as a single speed, but does run on chainrings sized for 9 speed systems.
Is your Cannondale's front chain the one you refer to as a single speed? Do you know if it is actually sized for single speed gears? Are you sure it is not the same size as your rear chain. (width, not length)?