BB Coaster mech?
 

I just got a bike out of the trash, its a Columbia Dream Machine 10spd. the rear casset is fixed and the bottom bracket houses the coasting mechanism. Ive seen alot of old bikes in my time but Ive never seen this before. What is this set up called? Ide like to learn as much as I can about this type of bike.

Thanks

The Front Freewheel System (FFS) was often coupled with Positron rear derailleurs, which were Shimano's first attempt at indexing... the indexing was in the derailleur and not the shifters. I understand that there were two versions, one with a single solid wire, and one with two cables. The RD has no spring...

The time period would be 1980 +/- a couple of years as I recall.

As others mentioned in the other forum, the FFS does allow for shifting while coasting.

I remember Shimano, I think it was, came out with this setup in the late 70's, if memory serves, but I do not remember what they called it. You might try the back issue archives at bicycling magazine's website, they may have an old ad for this crank and hub. If memory serves, they only made this for a couple years and then dropped it - like they did the internal geared 3 speed crank. The claimed advantage of having the freewheel in the crank instead of the rear hub, was you could shift while coasting or coming to a stop.

It does have a freewheel on the rear. The advantage is you can shift at a stop or while coasting. The disadvantage, more like a liability for Shimano, is a pants leg or shoelace can get caught in the crank while it was spinning and you are not.