Anyone replacing a worn or damaged 19T sprocket on a coaster brake hub.
Coaster brake hubs, the ones you stop by pedalling backwards, use a slip-on splined sprocket held on by a snap ring. This one has 19 teeth and is sized for 3/32 inch chain, as used on many kids' bikes, cruisers and single speed city bikes.
The three-lug centre locates on the hub driver, so it's a simple swap once the circlip is off. It's a handy fix for a worn sprocket that's skipping, or a way to fine-tune gearing on a single speed.
Fitting a new chain at the same time is always a good idea, as a worn chain will quickly wear out a new sprocket.
19 teeth
A common size on kids' and cruiser bikes.
3/32 inch
Suits narrower 3/32 inch chains.
Three-lug fit
Slides onto the hub driver and is held by a circlip.
Simple swap
Fix skipping or worn drive quickly.
Sprocket
Great for
Maybe not for
Check your existing sprocket's tooth count, chain width (3/32 or 1/8 inch) and the shape of its centre before ordering. Lay the old one on the new one to compare the lugs.
Swapping it over
Pop the circlip off with a small flat screwdriver or circlip pliers, slide the old sprocket off, fit the new one and refit the clip fully in its groove. Check chain tension afterwards, as a loose chain on a coaster bike can drop off and take the brake with it.
