FZRSupport: the FZROnline Archive

recently had the carbs completed dissasembled for a thorough cleaning (gummed up from sitting) and once back on bike ran good and idled normally around 900-1100 rpm approx. air mixture screws were re-set (after cleaning) at the standard 3 turns out. That was 3 mo ago.
Now all of a sudden idle is annoyingly high (approx 1800rpm fully warmed up) and I dont know why. Adluster knob is backed completely off linkage so thats not it. Could it be a rich mixture? ..or other internal issue with carbs? I know I still need to sync them with the tool but bench syncing should have gotten them close..Other than the high idle bike screams through the power band and runs as an FZR600 should.

Do an actual sync and then adjust the idle again. Is your float height to spec? I've notived with this cold weather my idle seems to be raised a litle bit but it is what it is...

Also Where in the world are you? Put your location in your profile as it helps members

Profile updated with location (miami)...warm temps here year round for the most part but this morning was cooler in the 50's. No, have'nt messed with float heights. I'll try syncing cause it needs it anyway (then recheck air/fuel mix) but suspect something else might be causing it. (Maybe a torn diaphram?)

Well with a torn diaphram or not quite seated you can take the airbox off and hit the throttle if you don't see the slides move or slide, you know which carb is giving you problems. Have you lookedat your pilot jets they are extremely easy to clog if the bike has sat for a litle and that may be. Somone wll come along and point you in a better position but that's where i'd start looked. Could be your thr9ottle cable are to tight? Just another though

Did you check to see if your choke is fully disengaging? Or keeping the butterflies open? Did you use the choke that morning? Either way it could have bumped loose. Another thing to rule out I guess.

Chris.

had a prob similar to yours on my xj, completly diff bike but it was the sync for me. i bench sync using paperclips. very good results for me. also while you have your carbs apart give the vacuum slides some attention. make sure they all drop down the bores and arent hanging up, there should be absolutely no hanging up or slow return to bottom with any of them. let me knw if you need a better explanation

check for air leaks with any flammable spray

Ok when was the last time you lubed the cables? A stiff cable will not let the carb butterfly's return fully to idle ?