85 xj700 Carb help

Hey, recently bought an xj700 as is with some issues (was a steal). The noticeable issues were a leaking valve cover gasket and hole in the carb intake boot (air filter to carb). I replaced these parts, and the bike starts up fine with high choke. However it will die soon after if you dont tease the throttle. Then when its hot it idles very high and bounces up and down. I rode it for about 20 mins as the idle revs continued to go higher and higher from 1500-2000 all the way to 3000-4000rpm at its hottest, when I turned it off. When it was revving that hot/high white smoke began coming out of the engine (rich indicator?). I do not think that the issue is in the idle adjustment screw because the idling is so inconsistent.

I know that the previous owner spent a fair amount of time cleaning the carbs, so I'm worried he may have done something wrong. Tomorrow I am going to check for vacuum leaks with some carb spray, but after this my technical experience is kind of limited. I am willing to be brave and dive in to the carbs since I just got my xjcd manual, but it would be helpful if people could point me in the right direction based on the symptoms I listed. Thanks in advance.

 

How many miles on the bike? Start by checking the valves and getting them in spec; because if they aren't you won't be able to sync those freshly-serviced carbs. That could actually be your problem.

You'll see that in all the service manuals on the CD; "valve clearances must be within specifications before synchronizing carburetors." Believe it.

Look in "FAQ Suggestions" for all sorts of tech articles to help you on your journey to reliable rideability.

Now, get some basic location info into your profile so we know what side of the world you're on; and the bike's info into your sig so we don't have to constantly ask.

And before you ride so much as one more mile: http://xjbikes.com/Forums/viewtopic/t=15874.html

 

Needing to run with some "Choke" during the warm-weather season is a clue that points to a Fuel Delivery issue.

Fuel Delivery issues are most commonly: "The Carbs".

A thorough Carb Cleaning will put you on the road to getting tuned-up right; but, you have to make sure Valves are adjusted and the carbs are Synchronized before you get truly tuned-up right.

Before we embark on guessing what you should or should not do, ...
Pull the Spark Plugs.
Place them in order, ... 1, 2, 3 & 4.
Side by side. Well lighted.
Take a photo of the Business-ends and let us see what the present situation is.

A photo like this one, please!