Carb rebuild?

Hi guys...new to the group with a 82 Maxim. I bought this bike in non-running condition. Did a handful of basic things to get it running but think that it may need some carb help.
I initially took them apart, cleaned em a little and stuck them back on and to my suprise the bike basically fired right up and idled about 1500 after not running for at least several years.
That didn't last long though...it now arbitrarily idles up to 5000 and won't come back down. No rhyme or reason. Sometimes it starts that way and other times it idles fine then races on up.
I looked for air leaks but can't find any obvious ones. Any Ideas?? Thanks

 

would seem to me that the slides are stuck.... can you control the throttle up or down any?

 

Mine had similar symptoms when the carbs weren't synchronized. It could be a vacuum leak also. Use an unlit propane torch, and gas the connections to see if your idle rises. If so, then it is a vacuum leak.

 

The throttle seems to work just fine, it's just that idle is sometimes way too high.

I'll give the gas test a try, I've never heard of that but I assume it's safe??

 

It should be safe. *Disclaimer - Of course, you are putting a combustible gas near a hot engine, so anything could happen* I did this without a problem. Just don't stick your face in it!

 

Only real danger is a loose wire that would cause a spark to ignite the propane. One other point, the RPM may rise or fall depending on the carb setting or amount of leak. Just listen for a change in RPM.

 

i tried the same thing with wd-40 and it worked

the bike came doen in revs after a few secs

then i decided there was a leak on boots

and apploed black silycone freely and fixed it!

 

I would also check your throttle shaft seals and vacuum hose to the fuel petcock.

 

WD-40 is more readily available and a little less flamable (but it is still flamable). I would chose the WD over propane anyday except when chasing an a/c leak (which we don't have on bikes and WD will not find a freon leak). Definitely check your throttle shaft seals as Rich pointed out, they typically have issues at this point in time.

 

I did the wd40 around the carb boots and had some get sucked in... tightened them down a bit more but the idle was still high... cleaned the air filter up some and made sure it was sitting in the air box properly... the idle came down a lot more but I don’t know how much if anything this had to do with it...
Tinkered with the idle adjustment bolt on the back of the carbs and the Rpms came down to ...
though my adjustment bolt doesn’t seem to do to much, turning it to the left has no effect... turning it a lot to the right will eventually make the idle race up to around 4,000 rmps