I have recently had my carbs rebuilt and synced, installed new spark plugs and fuel filter and ran Seafoam through my 87 Hurricane and still it runs rough (sounds like a dirt bike) and is low on power. Anybody have any ideas?

 

Check for exhaust leaks. Is it firing on all cylinders? Run it for a few minutes than either use an IR thermometer to check the header temps, or splash a few drops of water on each header. It should evaporate instantly.

 

When is the last time the valve lash was adjusted. I know when I got mine it needed it done. Also check the pilot jets they clog easy I had to pull my carbs out after cleaning them to reclean the pilots cause something got picked back up in them.

 

Did it run better before this work was done or has it been running poorly since you got it? If not already done I would check these things first:

engine compression
all cylinders for spark
fuel pump & filter

the IR thermometer is an excellent tool to use too if you have one, and you don't have to take the bike apart to find the location of the misfire

 

it ran great yntil i ran it low on gas twice. spark is good. I will do a few tests tomorrow. I am thinking maybe i should clean my gas tank fully to get the crap out if it.

 

Yeah thats a pretty indicative tidbit of info there. Clean the tank, new filter, and probably clean the carbs again.

 

Pilot jets in the carbs. Jets must be taken out to get them clean. Spraying carb cleaner and compressed air will not clean them out. You need to run a wire through the pilot jets to get them clean.

If the carbs are clean and adjusted right, valve adjustment would be next. All of the suggestions above as well. You can feel the pipes when your running to see if there are cylinders that aren't firing. Be careful though, they get hot. If you find one or more that isn't hot, your not firing on those cylinders.

 

both right side cylinders aren't firing. Looks like my carbs are coming off again.

 

Have you verified there is spark for those 2? But yeah, my money is on the carbs.

 

just before you take the carbs off, just check the connections under the tank as i'd got mine running perfect but after i was doing other jobs to it ran rough and sounded like it was only on 2 cylinders.
It turned out to be a bad connection on one of these plugs as i gave them a wiggle while it was running and you could hear the others burst into life and it ran perfect again.

It might not be the problem in your case but worth a shot

I've attached a pic of were they are, sorry its not a close up.