Hello,

I am new to the Gixxer forums. I recently took in a 1991 GSXR 750 for carburetor problem. It seems that it had a high idle problem. I took the carbs off the bike and gave them a thorough cleaning. I found the pilot system to plugged and cleaned that. The diaphragms looked good and raise when you raise the rpms. I have bench sync'd them and all of the butterflies are at the same #. I am getting ready to inspect the intake manifolds for any dry rot and cracks. I will also remove them and check the o-rings for possible leakage. Any and all help would be greatly appreciated. Larry.

Have you read the carb sticky thread? Set mixture screws? With the motor running you can check for air leaks by spraying carb cleaner around the boots and top of carbs. If revs go up you have al leak.

+1 on checking out the carb sticky. Helped me out big with mine. I cleaned mine and put them together bench synced them and had a heck of a time. It wouldn't idle, touch the throttle and the rpms would hang. It was doing this with the throttle cable disconnected. So I tried Fast cats way of bench syncing and it worked quit well. Open the butterflies using the idle adjustment screw then use a gauge that will just slide under them. They still wouldn't idle well till I brought up the fuel mixture.

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I recently won a battle with the carbs on my 1990 750 ,you may want to read through my thread ,I had seemingly tried everything and gave up for a while but won out in the end.

link to thread http://www.gixxer.com/forums/showthread.php?t=201360&highlight=1990+hanging+throttle

Setting sync buy feeler guage is only a base setting!! you still need to set by vaccum!!

You're right. Bench syncing is just to get it ready for vacuum testing.

Thanks all for the excellent tips on this forum. I pulled the carbs back off of the 750 and replaced all of the o-rings in the fuel bowls, bench sync'd them then pulled all 4 intake manifolds and found the source of the vacuum leaks. I made a run and picked up all of the o-rings, installed and put the carbs back on the bike. It fired on the first hit and immediately went to idle. Still need to run a vacuum sync on it to finish it. Thanks again for all of the help. LG. Kansas.

Happy days