I always used dish soap to clean the filter. As far as oiling the foam filter, I never oiled it. A 2-stroke engine spits enough pre-mix out of the carb onto the filter to “oil” the filter.
I have two kart stands for sale. One is $125 and other is $140. What is your location because I don’t want to ship a kart stand? My location is Zionsville, IN? Let me know.