Out on the lake today w/ 98 srx 700 w/ 4500 miles well maintained carbs & powervalves cleaned ect . She was running Great noticed power loss wouldn't rev past 7000 rpm sounded like it was loosing spark noticed a bubbling noise, so I pulled over I thought a plug wire fell off, all looked good pulled the plugs ( mag) plug looked blackish like carbon (ctr) nice bronze color (pto) carbon grayish,looked inside the plug hole no meltdown or holes in the pistons,started her up wouldn't Idle had to keep on the throtle , took it slow & got her back to the house & did a compression test (mag plug) was about 45psi (ctr) 125psi (pto) 115 psi . Has anyone had this problem. I know It was cold today, Possably ran lean ? but why not the (ctr) cyl ? poss both mag & pto seals at the same time? could it be the power valves in these cyls?or reed valves broke? Any help on where to start the diagnosis would be apriciated.