Also, Chris, the OS F is the plug of choice for mst four stroke applications.

And you engine should improve its idle after a gallon or so. The proper propellor is also important. Most new four stroke users tend to under-prop their engines.

A well-broken-in Saito 72 will swing a low-pitch (4 or 5) 14 inch prop, and this is what you want to best utilize the torque of your engine. The APC "wide" props are true stump pullers. The time and money invested in trying out some different props can be very educational and productive.

It can also be aggravating, but if this was too easy we wouldn't enjoy it as much, eh? I just finished spending many weeks and over $50 trying different props on my YS 63/SIG SE, just to discover that the initial one I put on there is the optimum. Oh, well... some days you get chicken, and some days you get feathers.