89 Johnson gt200 rpm and stutter issue

[Gt200]

Hey guys I have a 89 Johnson gt 200. When I first got the boat it pulled great running about 5500rpm at about 55-60mph according onboard speedo. I noticed gas and oil in the air box and decided to rebuild the carbs. I am pretty good with carbs and they are not that complicated. Since then I've been having issues hitting even 5000 rpms and about 45mph. It stutters around 3000rpms and again at full throttle. I've checked fuel lines, good strong spark with spark tester. Don't know what else to check. Thanks in advance.

 

[Gt200]

I have figured out my issue. After going the carbs, checking for fuel leaks, changing out the njk plugs for champions, and doing a link n sync. I finally boiled it down to timing. I timed my engine using joereeves method to 18degrees btdc (14 degrees btdc if using joereeves method) and it purrs like a kitten. Hope this could help someone. But what I have found in the years I've been diy mechanics. The most important thing to do is research, research, research and then cross your I's and dot your T's.