the arm shaft shaft and hook shaft are supported by ball bearings.
上下轴用滚珠轴承支承,同步齿形带传动。
note that the rocker arm shaft supporting seat with upper oil hole is at front end of the rocker arm and this end should align with upper oil hole on cylinder head rocker arm shaft when assembling.
应注意,带上油孔的摇臂轴座是摇臂的前端,装配时应注意以这一端和缸盖摇臂轴上油孔对齐。
it usess cog belt for arm shaft and hook shaft driving, dial typed stitch regulator and reverse feeding lever.