xj 650 maxim sputtering on acceleration

Colortune REALLY helped mine after valve shims and taking carbs to church. Once I dialed it in with the colortune it runs so much better.

 

carbs have been completely rebuilt. I also have new intake boots and gaskets. new throttle shaft seals. Its now somewhat harder to start and its worse with the sputtering. I did bench sync and vacuum sync. I tried dialing in the fuel air mixture and when I richen it out it sounds like it starts tapping on the valve side. I take the fuel-air back to the recommended setting and the tapping goes away.

I am thinking I have a valve problem. I am going to move the carb over to the parts bike and see if I can fire it up and if I can See if it transfers over to the parts bike. If it does then its carb if it dont then its in the engine. I suppose a leak down test would need to be performed to determine if its piston or valve right? New to this level of troubleshooting so any advice on next steps would be appreciated.

 

Your compression is low and it's the piston rings or cylinder walls.

Forget about the amount of oil you used. Assuming you did as directed by @chacal (no air filter, throttle open, no plugs, etc.), you have low compression. That you saw a rise in compression after adding oil into the cylinder means that your compression is low because of the piston rings or cylinder walls.