If you are asking whether you will "feel" enough with a 1 tooth change, you will. But when I had my RM125 I went from 50 to 52 teeth and it made a huge difference in how well it would pull. I went from a 48 to a 50 on my 99CR250 last year and liked the change. It tightened up the gap in the gear ratios nicely. If you are still unsure which sprocket to use, try buying a steel sprocket. They are dirt cheap and last forever. If you don't like the change, you are only out about 25-30 bucks.