I bought an 04 XLV back in February of this year with 510 hours and it has ran great up until the last 2 times i took it out. The last two times out it has ran fine up to the beach about 3 mile ride but on trip back while pulling tuber it has started busting up and bucking and backfiring like it is skipping or something but when I let off on throttle boat runs fine I can cruise back to dock at 13 to 14 mph with no issue but if I get on it or try to run above that speed for any period of time it will start busting up again. After first time it did it I changed out inline fuel filter the gas that I poured out had somewhat of a rust tint to it but after getting it home today I pulled filter and gas was clean and clear that was in filter. What should be my next troubleshooting step I was thinking maybe plugs wires distributor and rotor but they all look fairly new?