Question about carb sync on a 1986 interceptor 500

Forgive me if this has already been asked, and is a little long winded but I feel if I can give enough info someone can help me without have to ask twenty questions. My stepfather acquired a 86 honda interceptor 500 in 2003 the last plate registration was from 1994 from California I don't know if the bike was run in that time frame. The bike sat in his garage till 09 or 10 then my buddy asked about the bike and he ended up getting it from my stepfather. He pulled the carbs dipped them and I think he said he also did an ultrasonic cleaning on them and also changed the floats and some other things inside it sounds like he rebulit them. He put everything back together changed the fluids and started the bike he said that it started to rev real high and he shut it down before anything bad happend. As with everything when moneys tight somethings get put on the back burner and the bike then sat in his garage for the next year and a half or so until I got it back. I pulled the carbs off again and cleaned them and they looked brand new inside I put it back together and got the bike running and it would only run on full choke, thinking that I missed something I pulled the carbs again went through them aging and put it all back together same problem. I had read things here and there on this web site and came across a thred about seafoam put it in the tank and just let the bike run. I finally have the bike running off choke but the rpm's are around 800 to 500 I give alittle gas and it seem to fall on its face and die. I add alittle choke and it revs high and I adjust the idle set screw and get it to the 1300 +/- then take the choke off but still the samething it runs and stays running just low rpms. The question I have is this just a sign that the carb's need to be synchronized or am I missing something aging. I don't want to sync if I may have to pull them aging. I don't really think there is that much that needs to be done the bike has always been garage kepted and was not road that much it only has 8719 orginal miles on it.

 

Yes, if carbs are not in synch, the farthest open throttle butterfly will make a slow, steady idle impossible. You should have done a visual synch to get it close b4 you mounted carbs, but now they're mounted, you need to do a synch with manometer or dial gauges.

Did you clean out the mixture screw passages and reset screws to the initial setting, about 2 1/1 turns open ??

If you didn't poke a thin wire (.012" is about right) through the idle jets, they might still be partially blocked.

 

I am thinking I might have to pull them one more time. The orginal fuel filter that was on the petcock just fell apart, so I went and bought a inline filter to replace it. That was Sunday I was going through everything last night and noticed the the hose that had come with the filter was coming apart, almost like the gas was eatting away at it. I don't know how much or if any of the hose particals went down into the carbs. I have the cylmer for it but it only had the pilot screw settings for the 84 85 bikes at 2 full turns out, should it be 2 1/2? This my sound like an ignorant question but what am I looking for in a visual synch if I have to pull them again?

 

For a visual bench synch, line up the throttle plates so that they all expose the first small hole at exactly the same time.

Start by adjusting the master carb (with the idle adjuster screw) to show exactly 1/2 of the first hole under the edge; then set the others the same; then unscrew adjuster until you can just begin to see the start of the hole.

Flip the throttle wheel and let it close a few times, then readjust if necessary.

 

Thank You Sir. I did end up pulling the carbs again last night didn't find anything in them everything was clean. I'll tell you what I am getting faster at doing it only took me 2 hours to pull them off the bike and go through them and have them back on and the bike running. Did the visual sync and it was a pain in the ass trying to get them all close to the same such a small hole to try and match all the way around, but it seems to have done the trick. I did turn the pilot screw out one more 1/2 turn to make it 2 1/2 all together and put the air box back on and it seems to be fine, should just need some fine tuning. Now I just need new tires and chain the ones that are on there I am sure are the original to the bike as I said before it only has 8,719 miles on it and has been stored for the last 17 years at least.