2000 XP 951 Cylinder not firing

[2000xp951]

2000 XP 951 rear of ski cylinder rich? Ski won't rev past 3500rpm in water, starts right up accelerates up to 3500rpm then won't go past it, no hesitation on the throttle, things I checked both cylinders have 124psi compression, runs fine out of water with no load other then water going thru it with the hose runs past 3500 rpm out of water, took spark plugs out checked spark at night both cylinders have the same spark visually I took a video will jump from the strap of the plug about 1/2 gap to the head, checked to make sure there wasn't spark arching on anything while running didn't notice anything, rave valves were clean and operated with positive pressure on them rave check valve is good and lines don't leak vacuum maybe troubleshoot the solenoid? Didn't check to make sure they open when running yet, carbs rebuilt with vertex kit accelerator pump does work, pop off pressure around 23-24 on both carbs, the rear cylinder plug seemed to be wet when I took it out these were fresh plugs today br8es ran about 25 mins when I pulled them out for the picture, how is spark correctly checked? Something is definitely going on in the one cylinder maybe water getting in? It's either ignition problem or fuel related or head gasket bad on the cylinder any pointers would be great troubleshooting guides somewhere online maybe ?

 

[JC-SUPERJET]

First problem is that Vertex Carb kit...

Only Genuine Authentic Made In Japan Mikuni Kits work right.

Rebuild the Carbs right, then test again. Report back results.

Seen another case where a bad Voltage Regulator/Rectifier also limited the rpms.

After Engine operation, is the Rear Spark Plug cold compared to the Front Plug?

 

[Boyd12]

JC-SUPERJET is right, start with the carb kits. Mikuni are the only ones that work. I used aftermarket once and it didnt go well.
The clean plug could mean some water is getting into the combustion chamber. I would suggest pulling the RAVE valve and look for water on the RAVE valve and carbon deposits on the top of the piston. If there is water on the RAVE valve, and the piston top is clean, you COULD have a head gasket leak. Good luck!

 

[2000xp951]

JC-SUPERJET is right, start with the carb kits. Mikuni are the only ones that work. I used aftermarket once and it didnt go well.
The clean plug could mean some water is getting into the combustion chamber. I would suggest pulling the RAVE valve and look for water on the RAVE valve and carbon deposits on the top of the piston. If there is water on the RAVE valve, and the piston top is clean, you COULD have a head gasket leak. Good luck!

Found a pedal missing on the reed valve

 

[mikidymac]

That would be an issue for sure.