A rachet includes a round gear or a linear rack with the teeth, and a pivoting, spring-loaded finger referred to as a pawl that engages the teeth. The teeth happen to be uniform but asymmetrical, with each tooth having a average slope on one edge and a very much steeper slope on the other edge.
When the teeth are relocating the unrestricted (i.electronic. forward) direction, the pawl without difficulty slides up and over the softly sloped edges of one’s teeth, with a early spring forcing it (sometimes with an audible ‘just click’) into the depression between your teeth as it passes the hint of each tooth. When one’s teeth move in the contrary (backward) direction, however, the pawl will capture against the steeply sloped edge of the initially tooth it encounters, thus locking it against the tooth and stopping any further motion for the reason that direction.
Backlash
Because the ratchet can only just stop backward movement at discrete factors (i.e., at tooth boundaries), a ratchet does allow a limited amount of backward motion. This backward motion-which is bound to a maximum length add up to the spacing between the teeth-is called backlash. Where Ratchets Wheel Backlash should be minimized, a smooth, toothless ratchet with a high friction surface such as rubber may also be utilized. The pawl bears against the surface at an angle to ensure that any backward motion will cause the pawl to jam against the top and therefore prevent any further backward motion. Since the backward travel distance is mainly a function of the compressibility of the high friction surface, this mechanism can cause significantly reduced backlash.
This Ever-power 54t Ratchet kit works as a direct replacement and is super easy to install. Just remove the freehub body the parts you see here will maintain there, grease up the brand new parts and re-assemble the hub. Boom! You’ve just substantially increased the engagement tips on your hub. To give you a better notion of 
how this improves your ride think about the engagements in levels of a circle, with the 18t you’ve got to move the cassette 20 degrees to reach another engagement and with the 54t that knocks it down to 6.66 degrees! That’s less than a 3rd the length it needs to move to hit another tooth! You could be wondering when you can really start to see the difference. Only pedal your bike around and keep carefully the bike moving through the use of tiny pedal strokes and back-pedaling. You’ll see there’s going to always be lot’s of slop between engagements. Envision if that “slop” was decrease to a third! I’m sure you can imagine that is clearly a huge upgrade. Hence, if you weren’t already totally convinced on the 54t ratchet kit I hope this can be the turning point to getting one!