The crown or the chainring fixed on the right crank or on the bottom bracket of a BMX is one of the components of a BMX transmission that transmits the effort of the cyclist to the rear wheel.
This single-speed transmission consists of a crankset on which are fixed the pedals and the chainring which provides the mechanical force to the driver or the freewheel integral with the hub of the rear wheel of the BMX. The chain tension is adjusted by adjustable tensioners secured to the rear wheel axle.
Fixture of BMX race chainring :
For older bricross models, the crown of a BMX was crossed by the cranks and the crank axle which formed a block, in this assembly, an attachment point integral with the right crank drives the crown of the BMX.
For recent BMXs, the crankset consists of three parts, the cranks and the bottom bracket. A fixing star made up of four or five branches is attached to the right crank, it is intended to hold the BMX chainring.
Whatever the number of fixing points on a BMX chainring, they form a circle whose diameter corresponds to a standard. It is therefore essential to determine this value before choosing your board. The fixing of a crown of a BMX being simpler, its assembly is much more standard, it always consists of a hole in its center for the passage of the crankset and of a hole for the interface with the fixed pin. on the right crank.
BMX race gear ratio :
The value of the development ratio or gear ratio of a BMX allows to adapt the force and the velocity to be provided by the cyclist. Depending on the number of teeth of the BMX crown and that of the driver, the gear can be customized according to the use of the BMX whether in freestyle, racing or otherwise.
You will find in our blog article the formula for calculating a gear ratio as well as summary tables of the values.
BMX race chainring in a second hand or new condition :
We offer many chainrings and crowns for BMX of all brands and all standards regardless of your level of practice or the year of your BMX.
The choice of the value of a gear being a customization of the transmission of a BMX it may sometimes be necessary to test several configurations, in fact, the value of the development report is oriented by the practice for which it is intended but also and especially by the morphology and the level of practice of its user.
The BMX chainrings and crowns available in our shop come from destocking for those in new condition and revised for parts in used condition.
Here are the control criteria that we apply to each chainring or crown for BMX that we offer:
- Cleaning to remove dried grease and pollutants
- Visual inspection, search for any imperfections such as scratches or damage due to use
- Determination of the number of teeth and characteristics of the fixing points
- Estimation of the state of degradation of teeth and fixation points
Inspections and observations allow us to determine the general state of wear of the BMX crown which is rated on a scale of 0 (very bad for parts) to 10 (new with packaging).
BMX race chainrings brands :
Our supply channels do not limit the number of brands we offer, all major brands such as Haro, TA, Stronglight, GT, Redline,… are available. On the other hand, the quantities are often limited but the references are regularly renewed.