its a 1960 A7ss with the cast hubs, and a bob newby belt drive conversion for the primary drive, its very smooth but they only make the one size engine pulley which is for the A10 and its a bit high geared in top, so looking for suggestions on how to lower the gearing a bit, would prefer to change the rear sprocket, dont care about the spedo drive as i am not using that, got a gps spedo fitted.