what are these cranks ?

[big.eck]

i bought an old dawes roadbike to help me get a little weight off and started kitting it out with some nice bits and came across these cranks , never seen anything like them before but they look cool

anyone seen these before ? what were they originaly fitted to ?


cheers

 

[legrandefromage]

saw these on old Raliegh pioneers from about 1990

 

[Goldie]

I've always wanted to see round the back of one of those things. The eightiestastic design of the front sort of implies there might be a load of electromagnets powered by a teeny tiny nuclear reactor keeping the chain in place...

 

[jm]

Nothing fancy sorry just a steel ring.