For those that don't know, Solo 471 KAT is a German Backpack blower with a catalytic converter. This is not a well supported brand in US. I have been using it for 10 years and did change plug due to hard starting when hot. I still have the problem. It starts after about 3 pulls first start of the day. After running it for a while and trying to start it hot it seems flooded. Basically I have had to let it get cold to start it. Local shops do not work on these. Parts are like unobatinium. I am not even able to find a fuel filter replacement on Solo's website. It has a foam air filter which is clean. I have used Echo mix or Homelite mix at 50:1. I add an ounce of Seafoam per gallon of gas also. I will be getting fresh gas, but would a different oil mix help with starting? I found Homelite mix helped with a sputtering Echo trimmer compared to Echo mix. It takes a Bosch WSR6F plug, Champion RCJ-6Y or comparable. I am considering an E3 or First Fire plug but they have mixed to no reviews. I have had great results with NGK so that is another option. It takes an NGK BPMR7A. It does have some carb adjustments in manual (intended for service personnel only). But my carb has only one screw to open or close throttle for idle speed. I requires at least 91 octane gas. Would 93 octane tend to make it easier to start when hot or harder? Thanks in advance!