I have seen freewheels labled as "for flip flop hubs". Is there a difference between these freewheels and regular ones? Could I use a regular freewheel on a flipflop hub and vice versa?

I have seen freewheels labled as "for flip flop hubs". Is there a difference between these freewheels and regular ones? Could I use a regular freewheel on a flipflop hub and vice versa?

Narrower threading, perhaps, but I'd guess it's wholly unecessary. I'm sure you can use a regular freewheel (ie, BMX style) on a step-down fixie hub. I'd guess, though, that you cannot use a "fixie-specific" freewheel on a regularly-threaded hub without throwing off your chainline.

I have seen freewheels labled as "for flip flop hubs". Is there a difference between these freewheels and regular ones? Could I use a regular freewheel on a flipflop hub and vice versa?
What are you calling "regular"? A multi-cog freewheel? - TF

Flip flop specific if most likly refering to BMX hubs. The larger freewheel runs standard threading. The flop side with smaller freewheel runs a smaller diameter threaded section. 1 hub, 2 freewheels, 2 diffrent thread patterns.

Flip flop specific if most likly refering to BMX hubs. The larger freewheel runs standard threading. The flop side with smaller freewheel runs a smaller diameter threaded section. 1 hub, 2 freewheels, 2 diffrent thread patterns.

I assume there is different spacing and hub widths to match in the drops for track specific bikes and older geared road bikes that could be converted to single/fixed gear bikes. So, I am guessing now there is a multitude of hub widths, thread patterns and freewheels and cogs to go with them.


But now I am wondering if I could simply put any lockring or freewheel in place of a cassette body on the hub of an old wheel? What is compatable and what isnt (assuming 3/32 chain). Will different ones affect the chainline differently? And do flip flop hubs for road bikes have different thread patterns on either side?

As was noted, a flip-flop BMX hub has a narrower side to accomodate freewheels with less than 16 teeth.

Road flip-flop hubs have either two sides threaded for freewheels or one side that is threaded for a fixed cog and reverse threaded for a lockring.

The flip-flop specific freewheels you see are most likely for the narrow side of a BMX hub. Another variation is the LHD (left hand drive) freewheel. Other than those two, I am not aware of variations in threading. Standard BMX freewheels are 3/32", and AFAIK there is only one chainline spec.