Classic & Vintage - Shimano Unishift Question (Front Freewheel)

I bought a 80’s Schwinn Varsity that I intended to use as a fixed gear bike because of its unique drivetrain, the rear cog is fixed (sort of) to the hub. I was simply going to swap the crank, and wah-la, I would have an inexpensive fixed gear bike. Well I posted the bike in the Fixed gear forum, and the consensus is it’s a bad idea. Perhaps even unsafe.

Can anybody think of a reason I should keep this Shimano drivetrain? Is there anything cool I can do with it? Does anybody run this system? It’s the Shimano front free (FF) system. The Cog set is fixed like on a fixed gear bike. The "freewheel" mechanism is integrated into the bottom bracket allowing the bike to coast. In otherwords, your crank arms are not mounted to the chain rings. While coasting, the chain rings are spinning beside your ankle. The advantage is you can shift while coasting. I think this was also called Unishift.

I'll be watching this thread as well; I just picked up a 1983 World Tourist -- the model with painted fenders and mattress saddle. Kind of a Suburban with lugs.

The Cog set is fixed like on a fixed gear bike.

I gather you are running the bike as a singlespeed, but not a fixed, correct? If so, there's nothing to worry about.

However, if you ever remove the "Front Freewheeling System" (that's what they called it) in favor of a standard crankset, be aware of this:

The FFS freewheels were equipped with an emergency catch that allowed them to freewheel if too much reverse force jammed up the system, such as getting your pantleg caught in the front chainring. As a result, if you try to slow the bike down with the fixie method of putting force on the pedals rearwards, the cogset will come unlocked, and begin to freewheel - a nasty surprise at the least time you want it.

If you run it with the original freewheeling freewheel though - you shouldn't have anything to worry about.

Take care,

-Kurt

I picked up a Raleigh Rampar to flip a while back that had the front-freewheeling system. I don't think it really matters whether you keep it or not...at least I don't know of any reason you should replace it before you need to. The bike I had weighed about the same as a walmart mountain bike though, but whether it was due to the FFS I don't know. And if I remember correctly, the BB shell was wider, as in 1-piece crank style, altough I could be mistaken.

I thought the Varsity was electroforged.

Schwinn, so many versions and models!

OK, so the general consensus is the FFS rear hub/cluster clearly wont work safely in a Fixed application. Oh well, it rides fine as a single speed right now. Thanks

I thought the Varsity was electroforged.

Schwinn, so many versions and models!

Yeah, and then there's the aluminum Varsity!