520 rear sprocket 41-46 teeth for BMW HP4
serial rim (520 racing chain conversion)
light racing rear sprocket from very strong aluminium alloy (aircraft alloy)
From different producers with proven racetrack experience (e.g. Esjot, JT, etc.)
Fits for:
- BMW HP4 (all)
(520 chain conversion / serial HP4 rim)
Measures:
inner diameter: 70 mm (76,5 mm at the heel)
bolt circle diameter: 100 mm
number of bolt holes: 5
Serial bikes are often equiped with a very long gear transmission due to noise or exhaust regulations. In most cases these transmissions don´t fit best for racetracks. Often pinions with 1-2 teeth less and / or rear sprockets with 1-3 teeth more are used. In some cases a longer chain is needed. Only on racetracks with very high speed (e.g. Isle of Man, Hockenheim GP) and very narrow tracks (e.g. Fischereihafen in Bremerhaven) such an conversion will not fit best.