minor adjustments?

[WADE NORGAARD]

i have an 88 2 stroke with a fresh rebuild on the cylinder,piston,rings and seals.
all new fuel lines everything went together great, started no problem, running a little richer of course for first tank, test drive was good except it didn't seem to fill the fuel filter to fast while running but it was flowing and i had forgotten the throttle spring on cable to keep it steady cause it was full throttle or no throttle and real hard to keep at a steady speed. i WAS getting wot but put a spring on it and adjusted the length so it wasn't adding fuel before the microswitch had clicked. now it gets to about half throttle and no more acceleration. if i jack the back end up and run it i can get full throttle but under load no bueno. it doesn't backfire or run like crap. i'm thinking float issue? not smoking as much as it should i think either. oil injection pump deleted , just mixed gas.
FYI the carb on the cart is not the one listed in manual. only difference is no adjustment screws whatsoever other than idle stop screw. carb was totally disassembled and cleaned as well as fuel pump.
any tips or things to try would be greatly appreciated

[slonomo]

Aftermarket carbs are not great, OEM are the best. I have seen carbs cause all kinds of issues like this. What oil mix ratio are you using? I think factory is 128:1. Any more than that is too much unless you are breaking in a new engine, then consult the manual. Break in is usually 50:1 or so for a short period. Oil buildup is a problem on these. Another fuel related issue is the fuel pumps. If it's old replace it. I learned recently these sometimes will leak at the diaphragm and pump fuel into the crankcase, had it happen on a friends cart, it was literally filling the crankcase and caused starting and running issues, so much fuel.

[WADE NORGAARD]

I recently replaced the fuel pump, no change. I adjusted the float back and forth to seeing if it made a difference but no. Like I said , it starts no problem, I warm it up and take for a ride on pavement and it just doesn’t do anything past 1/4 to 1/2 throttle. It doesn’t start stalling or anything when I try wot , it just doesn’t accelerate. Then I jack up the back end and start it up and it’ll go full throttle smoothly. I’m not a big guy so I’m not overloading it. Also, I am running at 50:1 cause it’s all new cylinder, piston, rings , crank seals, sealed the crankcase halves . Is it possible to blow crank seals even if they are new? If so , would that give me the issue I’m having? Why does it do it under load? Need help, don’t want to keep throwing new parts at it even though the only thing left that isn’t new is the carb ??????

[JPonLKN]

My first question would be, what were they symptoms prior to the rebuild, or why was the rebuild performed? I assume it was either not running or running poorly, but was it the same stuff? If so, I'd lean toward the carb. If it was running well, and a seal failed, then not the carb.

If it was getting WOT after the rebuild, but before the addition of a spring, I would look there first. See if removing that spring will allow you to get your WOT power back. If not, that isn't the issue and maybe your loss of power is in the rebuild? Check compression, and plugs. Might have fouled your plugs already.

[WADE NORGAARD]

It was in pieces when I bought it and half the crankcase was cracked so I found a used crankcase online and used the half I needed so I didn’t have to press the crank out. Put a new rings new crank seals and just cleaned everything up and put it back together went for a ride everything was fine I was getting wide open throttle then all the sudden it locked up so I pulled it all apart again and one of the wrist pin snap rings had come out of the groove and the cylinder was screwed so I got a new cylinder new piston and rings. FYI The only thing I didn’t disassemble but also didn’t inspect. So, the carb did work pre rebuild. I didn’t replace the fuel pump gaskets or carb gaskets as they seemed fine. Possibility?? Wouldn’t it run like crap regardless if there was a load on it or not? Guess I could spray something around those areas and see what happens. Another thing, how wet should the plug be if I pull it out right after running it. If it all . Can’t say I’ve ever pulled a plug from a recently running engine only when they don’t and are flooded

[Bbr]

Choke issue? air filter?