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01 Rubicon Poor top End Power

1013 Views 1 Reply 2 Participants Last post by  spock
I have owned this since 2003. It's never let me down... Until now. I'll admit I have never done any major work on it. I'll clean the carb every year or so and change the oil as needed, but nothing else.
It all started with a simple top end rebuild. Almost. I used the existing cylinder and just honed it. I put new (stock-size) rings on the existing piston. I reworked the heads (lapped the valves, replaced valve seals). Set valve clearance and rebuilt the carb.
After reassembly, I was able to get it idling great with minor adjustments. I put the plastics back on and took it for a spin. It is slow to rev up and has greatly reduced top end power. I did a compression check (dry) on it and got 65psi. I understand that this is normal(?). The wet compression check is at 125psi.

I have not made any adjustments to the carb (pilot screw).

Looking for recommendations. I know I'll get a lot of responses on reusing the cylinder without machining it. That is expected and I feel may be the answer, but before I put another $450 into it, I would like to make sure I am not overlooking anything obvious.

Thanks in advance
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I doubt that using the cylinder & piston again would be an issue since the compression is still ok. The "wet" compression you tested: did you just get the engine warmed up & then test it? All I would suggest is rechecking the cam timing & also have a look at the carb diaphragm - it might be cracked.
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