My 99 rm125 did the same thing. The clutch basket on the Suzuki's are terrible. When you take it apart I am positive it will have grooves cut in it from the plates. Draw filing the basket will fix the problem temporarily. But it will happen again even faster the next time. If you want a better solution, get a hinson basket and the problem will disappear. I loved the powerband that your bike has. Pretty good low end for a 125, and handled like a slot car. I still miss it!