Thanks for the part numbers. 12 dollars for a little jet Oh well it's only money. What exactly doese the leak jet do and why would going from a stock 70 to a 40 make a big difference? Try Sudco, they're about $8. I just orderd 3 mains, 3 pilots, 2 pilot air, 2 leak, & 1 starter jet from them yesterday, for about $50 shipped. Much cheaper than Yamaha.