Curious about these 18mm freewheels you see on aliexpress and ebay etc.

Page may contain affiliate links. Please see terms for details.
I've seen a few of these for sale but have no idea what they are used for except one was mentioned as for single speed/fixed gear bikes (flip flop hub?). I noticed 12 people were watching a ebay listing for such a freewheel. Anyone any idea? Looking at the image below it looks like it may screw onto the axle itself and you load that cup bit up with ball bearings. I googled 18mm freewheel fitting but nothing came up, maybe its actually an imperial measurement I should be googling. I wonder what the advantages and disadvantages are of this type of freewheel. Maybe its just small thread designed for childrens bikes in China or something but then why sell them in the UK and why are so many people watching the listing. From what I have seen the cup bit as shown below is on the outside of the axle with the thread more towards the middle of the axle. It seems likely it spreads the load more effectively compared to normal freewheels, possibly for BMX bikes or something which take greater impacts as it seems like the bearings will be further out like a freehub. There is a surprisingly lack of information about these freewheels but then perhaps I'm not googling the right description. Also I've not seen any part that increases the thread of an axle to 18mm to take this freewheel size either although some of the plain tube spacers you put on normal rear axles are 18mm in diameter but without threads. Maybe its to do with Chinese style e-scooters with pedals that have thicker wheel axles.

https://www.ebay.co.uk/itm/154299101427


s-l1600.jpg
 

Cycleops

Legendary Member
Location
Accra, Ghana
Your curiosity will take a tenner to satisfy. Go for it.
 
Top Bottom