Hey all. I just picked up an 87 Hurricane as a craigslist trade for a lawn tractor I had. I've been around bikes for most of my life. I have lots of experience resurrecting barn finds. My current bike is a 77 yamaha xs360 cafe'd with a fiberglass bum-stop seat I build myself, rear sets from an R6, and a 2 into one underslung muffler.

So after I picked up the Hurricane, I stripped the plastics and pulled the carbs. They were filthy, so I stripped them and cleaned everything. Reassembled the bike and she fired up. Idled high with the choke on as it warmed up, idled rough once the choke is off. So I get out the mecury sticks and get ready to balance the carbs. On my bike, #2 is the carb the other carbs are set to. With the vacuum gauges hooked up, #1, #3, and #4 look normal. The mercury bounces a little bit, but basically steady. But #2 barely moves. It climbes to a normal vacuum reading, but doesn't fluctuate like the other carbs do.

I shut everything off and using a length of tubing hooked to the test ports, I checked to see if I could blow into each port and yes, I sucked on them as well. There's no way to type this part without sounding ghey.

All of the carbs were free flowing through that air cut out circuit EXCEPT #2. So I pulled the carbs off, separated 1 from the rest and removed the air cut out diaphragm. I blew air through all the passages and could get a tiny amount of airflow through the nipple, but not nearly as much as the other carbs (I pulled the air cut out diaphragm out of the separated #1 carb as reference. Air roars out the nipple if it is applied to the proper port behind the cut out diaphragm). I used a guitar string to lightly prod around the #2 air cut out ports and nipple with no change.

So my ultimate question is, is #2 metered somehow to keep a steady vacuum reading to make it easier to synch the rest, or is this a restriction that I need to deal with.

I'm thinking restriction because with the carbs back on the bike and running I have vacuum on the sticks, but the carbs don't idle down smoothly (like a slide is hung up, which is not the case) and #2 pops and spits back at idle intermittantly, like the cut out circuit is allowing extra fuel.

Also, what's up with the pilot screws? They aren't covered with caps, but they are only allowed 1 revolution from stop to stop. Does anyone know if they are already set 2 turns out and I am adjusting between 2 and 3 turns, or something like that?

 

Welcome & nice find. Good luck with the rebuild, it sounds like you know stuff. The tech guys will chime in soon to help you out as there are many gurus here.

 

No 2 carb has no adjustment you are supposed to set all the others to it.
Not sure on the rest
www,blackbears.ru
or
www.carlsalter.com for the manual
Welcome to the asylum !

 

As SHADOW said.

See my link for video on carb balance below.
This has same carbs as yours.
See here for what mine looks like on #2 compared to the rest and you can determine if you have a problem or not ... http://www.youtube.com/watch?v=D2JNB...eature=related

 

Thanks guys. I have the manual, and I found your video on youtube. It would appear that my port is clogged, because your readings all respond the same to throttle blips.

I hooked a long hose and funnel on the end and let some cleaner soak through it. It opened up a tiny bit, so I should be able to get the synch done.

But if that port is normally capped off, and the port in the throat of the carb and the air bleed port are clear, I shouldn't have a running problem, just difficulity in synching the carbs.