Unleaded / Super Unleaded.

Best to read the instruction booklet for petrol recommendation. Ours is definitely super required as regular puts too much wear on the engine. We got a good one brand new (expensive) and don't plan to ruin it by saving a few pennies on petrol. Your booklet will also tell you the proper oil to petrol ratio. If you haven't the booklet, try online as many brands will post this sort of info.

That doesn't help the owner much does it as super and regular are both unleaded these days. I wonder if part of the start up problem is because you've used regular in the past? Most 2 stroke engines take regular but there's something about strimmers that requires super. We had to buy a special little petrol can just for super for our strimmer.