1990 FZR1000 hesitates

[m6969thompson]

I need some advice. I have my FZR which isn't running to well. I bought it basically new with only 2k miles on it about 24 years ago. It only has about 7k mils on it now. It hesitates with too much throttle. I have replaced the coils, spark plugs, ignitor, fuel filter and pump and air cleaner. I always suspected the carburetors and just sent them out to be rebuilt by a reputable dealer in Florida. If you easy into the throttle bike runs ok but when quickly twisting the throttle it will hesitate and you can hear a slight flutter. Best test is at cruising at 50mph and if you crank the throttle it feels like it's running on three cylinders or something. The diaphragms were inspected and were ok. Something is not functioning properly with a quick opening of the butterflies. The bike is completely stock. Stock air cleaner and the EXUP was also checked. The carbs supposedly have all the stock jetting. I'm suspecting clogged jets or air orifice, needles, tubes out of spec. I wish i had a known set of good carbs to try. Any advice? Thanks a lot, Dave

[Fizzinatorr]

What do your plugs tell you? I'll look around for the plug chart I believe its in the clymer

[m6969thompson]

Thanks. All plugs look the same. The bike recovers as soon as you back off the throttle.

[Stig]

had a similar issue lately after the bike being laid up over winter

Mine turned out to be a combination of worn emulsion toobs and a blockage in the pilot circuit
Over winter i swapped the emulsion toobs which helped the throttle response but there was still the lag that made the bike feel not nice to ride
I then ultrasonically cleaned the carbs but the issue remained

A few weeks back Roadrunner and nuggitt came down to my place and the 3 of us swapped parts over...coils, plugs, leads and various other bits were checked

We eventually decided on a full strip of each carb in turn, cleaning and blowing through every passageway with high pressure air line. Everything was re-assembled and the problem was gone
The issue was only on the first 1/8 -1/4 throttle but cleaning the pilots and associated toobs seems to have cured it

Hope this helps

[m6969thompson]

Are there any fuel injection conversion kits for the FZR1K? Thx

[m6969thompson]

thanks STIG

[DonTZ125]

Are there any fuel injection conversion kits for the FZR1K? Thx

Not yet ...