1982 GS550 L eratic idle problems

[jrl1982]

Hello i am new to this site and also a new rider, I bought my first bike last week and its a 82 suzuki GS550L it has 13,000 miles on it and its in showroom condition, my problem is that when im driving the bike and i pull the clutch the idle can sometimes be up to 4000 rpm and stay their and other times it will be around 1100 rpms, i have replaced the intake boots with brandnew ones new clamps and o rings,also i pulled the carbs and they seem to be very clean and their is nothing pulling on the throttle cable, could it be maybe the carbs need to sync'd ?

[tom203]

Welcome. Do you know any history regarding this bike? i.e. any clues to maintenance (or lack of) ? It might look "showroom condition", but it's 31 years old! Carbs can look clean but the passages you can't see can easily get gunked up. If "choke" circuit allows too much air to flow when it's off, revs can jump.
But as you apparently know, typically erratic idle like this has to do with those intake boots and o-rings at boot/head interface.
Does it cold start ok? run down the road ok?

[Nessism]

Of course the carbs need to be synced, along with all the other maintenance 31 year old motorcycles need. Valve adjustment for example (before the engine is damaged).

The 550's typically need their pilot screws set at 3+ turns open to avoid a hanging idle. Since you have already cleaned the carbs this adjustment should be easy.

[jrl1982]

thanks for the replies I ended up removing the carbs and completely cleaning every hole and jet with carb cleaner and using compressed air to blow out the passages i put them back together and reinstalled them, i also noticed when i took the carbs off that 2 of the boots on the air box were not connected to carb number 2 and 3, but those are secure and tight now and now the bike runs excellent i took it for a ride today, i will check the valves here to keep on top off that