High rev cold starts with RB carb mod

Mar 6, 2002
Since I installed the RB modified carb on my '02 220, I experience high rev cold starts with the choke on. Releasing the choke half way will slow it down but I need the half choke to keep it running until it warms up (60 seconds). After it warms up, it runs great and the plug looks good. I have not adjusted the carb since I received it from RB Designs. Is this a result of a lean pilot jet or is this common for RB modified carb?