as losiu was mentioning, I was having exactly the same problems with my clutch starter, and thanks to this post I was able to fix it by own spending few $ for the spring
below I am attaching few photos:
- after taking out flywheel, clutch was totally destroyed,spring was broken and those small stones was everywhere
- I realized as well that flywheel is little bit demaged, and 'stones' are not having initial/oryginal shape
but finally I have decided not make anything with flywheel, and stones, I have replaced clutch spring only, mounted everything back and till now(more than month, I am ridding almost everyday) it works fine!!!
losiu, thanks for this post and help