There are some things about BMX I take for granted, and I’m sure I’m not the only one. It’s when I see people asking questions about things like engagement points that I realise while it might be simple for some of us, there are others who haven’t been introduced to the technical side of BMX. They say ignorance is bliss, and well, it does help keep things simple but that said let’s talk about engagement points.

There are two main types of hubs for BMX racing. There’s the threaded hub, which is very simple and usually a cheaper option. The driving unit is called a freewheel which simply screws on to the thread of the hub shell. The other type is called a cassette hub. The driver mechanism is built into the hub. Some examples of cassette hubs are Profile Mini & Elite, Alienation Royal & Thrust.

In the case of both the freewheel and the cassette there are varying points of engagement. The Shimano standard is 30 points of engagement. What that means is your crank could rotate up to 12 degrees before you get any drive from your wheel. The lower the number of engagement points the more the crank will rotate before your wheel will drive.

There is a term “instant engagement” which implies that you don’t have any lag before you get drive from your wheel. The thing is there are very few hubs that provide truly instant engagement. There are a lot of hubs that people refer to as instant engagement, but the truth is they are not. They can have anywhere between 30 engagement points and truly instant engagement, so the term “instant engagement” is used loosely.

True instant engagement hubs are at the top of the pile when it comes to price. Will instant engagement make you an Olympic Gold medal winning rider? No. Over a 400meter race the gains from more engagement points will be minimal, but in a race where 0.1 of a second could put you on the top step on the podium the advantage may outweigh the cost.

Personally I am as comfortable on a hub or freewheel with 30 points of engagement as I am with any other alternative but then again my BMX racing is more about having fun than winning medals.

Some examples of engagement points in Freewheels

Some examples of engagement points in Cassette Hubs