93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
exactly as the title says, I just purchased the bike last week. It won't stay running on its own the "Idle knob"? does not appear to do anything when you turn it. At a low speed on steady throttle it seems to surge or jerk, but when you nail it, it goes fine. any tips?
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
Quote:
Originally Posted by gsxrgary
exactly as the title says, I just purchased the bike last week. It won't stay running on its own the "Idle knob"? does not appear to do anything when you turn it. At a low speed on steady throttle it seems to surge or jerk, but when you nail it, it goes fine. any tips?
Carb cleaning is in order. Check out the Oil-cooled's sticky "Understanding carbs" as a guide...any other q's we'd be glad to help you with...
Write down the jet sizes you find in there too for future reference...
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
mine did the same before i cleaned the carbs (also using seafoam in the gas)..helped alot, but i am still going to get the carbs sync'ed..get some sea foam..it will help
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
ooo..that can definatley cause an issue..double check all your connections ie. choke, idle ect ect..maybe one is really loose, or disconnected..i mean if its adding some choke to it unintentionally, that could cause sperattic power output..(not sure, just a thought)
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
well I took the carbs out cleaned them and found a large house fly stuck in the main jet of one of the carbs. It rides good but still seems to jerk violently when trying to go a steady slow speed. Also I found that the number 4 carbs diaphragm and slides were sticking causing the bike to stay at about 4500 rpm until you put it in a severely low gear to bring the vacuum down to lower the slide. all of that is fixed but the jerking is still a mystery to me. timing? valves? plugs? any suggestions?
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
Just how low of speeds are you talking about?
My bike doesn't like steady throttle below 4000 rpm either...it starts jerking so I need to clutch in...I know my carbs are 100%, just completely redone this winter.
I always thought this was normal on these bikes seeing how they are meant for higher rpm operation, not a ton of slow "in town" riding...
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
Did you pull all diaphragms and remove needle jets and soak the carbs in Barreymans carb cleaner? A 1 gallon can is 20 bucks at auto-zone with a parts cleaner basket lasts forever just keep the lid on tight. After soaking each carb overnight blow out all passages with a can of carb cleaner or just compressed air. Now replacing broken gaskets and all o rings as needed (Ace Hardware) re-assemble all carbs and fill directly into the gas feed hose with carb cleaning solution till just before the needle and seat shuts down flow. Now plug all overflow lines and blow air through the gas fill line making sure air flows thru the needle and seat(ie. bowls not full to the top. Looking at the flow coming out make sure no carb has any plugged passages, if you find a plugged passage squirt more carb cleaner directly into the plugged passage until all carbs flow evenly. Now start with the # 2 carb and adjust its butterfly by eye, so its even with the #1 base carb. Go down the line like this making sure all carbs are close to opening at the same time. This is all that's needed for a free Sync! If its stock jets stock pipe and air box go stage 1 jet kit. Make sure the bike shop stocks the Float bowl gaskets. The jet kit will get rid of all hesitation, but will kill fuel milage!
Good luck
Hardtail
Re: 93 gsxr 750 won't idle, chugs and jerks at low speed with steady throttle
sounds like your bike was doing the same thing mine was. i thought it was an ignition problem. so i changed the spark plugs and as i was changing the #4 and #1 cylinder's wires i noticed the orange wire going to the coil would not stay on. so i bent the metal a bit so it would stay attached to the coil and i never had a problem from it since. try it on both coils and tell me what happens