Question for where to go next..

bench synch. http://xjbikes.com/Forums/viewtopic/t=6366.html
That link covers it pretty well. Substituting strips of business card for the paperclips will get the butterflys set much closer to where you want them for the first startup. You will do a running vacuum synch once the bike is warmed up and idling without using the choke.

 

Okay, bench synced the carbs by setting butterfly levels, all float levels are within spec, bike fired right up, but once warm still won't idle without a little choke. Ideas so I can get her to idle warm without choke for vacuum sync?

 

Sounds like vaccum leak while its trying to run spray a bit of carb cleaner on areas like throttle plates, intake boots, etc etc. Is this liquid or air cooled? Forgive my laziness for looking.

 

In addition to the possibility of an air leak, you should also check for good spark on all four (it should idle OK on three though), and cracked plug wires or boots. Not all air leaks will show up with just a spray test; get a Gunson Colortune if you don't already have one, so you can see what the mixture looks like.
DOn't forget to check the vacuum vent plugs, the petcock vacuum line, and the vacuum valve on the petcock itself.

 

So, bike still won't run without a little choke. Seeing as I know my float levels are correct, after thinking about it I agreed with the thought that it was probably a vacuum leak. Sprayed her down with WD-40, but no change in RPM. For the hell of it I grabbed a can of carb cleaner and sprayed around a bit. The line from the petcock to the #3 engine side boot where the line meets the boot has a leak. RPM would rise every time I sprayed there. Also I bought a vacuum gauge and (from the right side of the bike looking forward) #4 engine side vacuum line hook up was running about 4" Hg. #3 was 3-3.5" . #2 had the line from the petcock and #1 was about 2-2.5" Hg.

I'm going to replace the leaking line and see if that makes a difference. I've yet to order a Gunson colortune, as the shops around here do not carry it or even know what it is.. So I will have to make an online order for it.

 

Well, replaced the line. Still same symptoms spraying there with carb cleaner. I'm thinking it's the boot between engine and carbs.

 

Well done for persevering- keep us posted with the progress. I fear I'm in line for a dose of this soon..

 

excuse my laziness, but were you able to see thru all 4 pilot jets? Did you spray the carb clean on the spring on the shaft between the carbs? That is where i had to spray to get mine to spike...due to throttle shaft seals.

 

Revisit your bench sync. Compare the positions of the butterflies to the tiny holes in the top of the carb throats rather than trying to use a "feeler."

And be sure you set the floats to spec, not just all equal with each other.