recently we switched to an air diaphram system but when we used the 12 volt Fatboy we added the Flojet accumulator tank and successfully used smaller tips when needed and also were able to adjust with a ball valve as well with no problems.
I spoke with Bob from pressure Tek regarding some concerns I had with the Fat boy but assured me the accumulator tank would allow me to use whatever size tips etc. I figuring/hoping that will help me avoid burning up motors. Bruce does your set up have the accumulator tank?.
Yes and it works great you can cut back with no problem.