UK Official Gearing Chart
birelART UK races are run with a set sprocket.
birelART factory drivers have tested with the correct weights, chassis set ups and have evaluated each circuit before the sprocket is set.
This is done to stop high RPM being achieved by engines and consequently reduces engine wear which results in avoiding costly rebuilds.
The Iame EK engine rpm is normally set so that the max revs met are between 14,800 and 15500 rpm. By limiting the rpm the engine performance is still impressive and helps achieve the Iame EK engine service schedule times.
In birelARTJunior100 / Super 125 the front engine sprocket never changes and is always 11t, this must always be the original Iame sprocket.
The rear sprockets for birelART UK race tracks are:
|TRACK||ELITES125||JUNIOR100||CZ CHAIN LENGTH|
|Clay Pigeon||77||77||100L to 102L|
|Ellough Park||85||85||106L -108L|
|Glan Y Gors||76||76||100L to 102L|
|Lydd||82||82||104L to 108L|
|Llandow||83||83||104L to 106L|
|Forest Edge||85||85||106L to 108L|
|Rowrah||85||85||106L to 108L|
|Rye House||85||85||106L to 108L|
|Whilton Mill||81||81||104L or 106L|
|Rissington||81||81||106L to 108L|
|Shenington||76||76||100L to 102L|
|Buckmore||85||85||106L to 108L|
|96L to 98L|
At some circuits the front sprocket on a birelARTcadet 60 which is 10t as standard is sometimes changed to an 11t.
|Track||Rear Sprocket||Front Sprocket||Chain Length|
|Glan Y Gors||73||11||98|
|Shenington||73||11||96L to 98L|
N.B The sprockets quoted above are correct at this time, always check
the Official sprocket Bulletin before entering an birelART UK series event.