Special steel Medium spring 3.0 mm 1/5 On road
Recommended minimum preload at 0.7, maximum 1.3 +/-.
The pre load changes depending on some parameters:
-engine power
-engine capacity 23 cc/ 26 cc / 29 cc
-different use of rollers art 150270 or 150280
-different shimming of the bell clearance art 150300
-different shimming between art 150200 and bearing art 500140 positioned under the bell housing