Here's another update in case anyone has been following or is looking for potential solutions. 1st off, i picked up a 1992 vxr with aftermarket head, exhaust, and all for $250 so i could have parts and a trailer for the 650. The parts ski ended up running after cleaning the carb and changing spark plugs. Its problem was that it sputters anywhere after 1/2 throttle and didn't rev any higher after that point. I rebuilt the top end and all the cooling/water channels (the outer rings surrounding the cylinders) in the head were full of shells. I cleaned everything and put it back together. Still had the sputter, so I decided to redo my fuel lines and shorten them, so I plugged my ON line and ran a line from my RES to filter to carb (this was to guarantee my fuel switch wasn't bad and to reduce the time it takes the fuel system to pressurize after starting). I also tried different known working ignition coils and they made no difference. It still goes up to 1/2 throttle and doesn't really rev higher, but it seems to go slightly faster (30-35mph) and no longer sputters, it just doesn't rev up. I was thinking maybe the temp sensor is bad and acting as a rev limiter. Thats what i'll look into next.
Also, the 650 i figured out had a stripped bolt on the head and a bad head gasket leak, which explains the wet plugs, terrible starting, and terrible running. I tried to re thread the cylinder block and my tap broke off into the block, so I'll be buying a new one of those off ebay when i find money. Lastly, the 700 would only kinda start like once a month. My friend suspected it was ignition coils, so i let him try one of mine, and before we knew it he was flying across the lake going 45mph! His only problem is carbs right now. It idles great and goes full speed, but everything else is sketchy. So here are some questions that i can't figure out...
If his ski is set at the exact point where the low speed screw is at its highest possible idle (it wont hardly run on any other setting) but when he give is gas it starves (I believe it is starve because he needs to poor gas in the carb to start it again), than his popoff must be decreased in order to allow more fuel, correct?
Also, is it possible that a bad heat sensor would restrict the engine from reving past 1/2 throttle? Or is there another likely source?