take the carb off, complete take it apart, clean it out complete, there are two jets, the main and pilot, take them out and see what numbers are on them. clean them out and jet out the hole they came out of. put them back in. also check the needle and clip position. write down this info too. also check the float level, it needs to be at a certain position too.
just take lots of pictures while doing this and if you have trouble we can help you put it back together.