86 GSXR1100 farting on cylinder 4.... help
Hi - I have an 86 GSXR11 that is farting on part throttle on number 4.
Start bike runs on 3 with 4 half running and farting.
I have tried the following.
Swap leads 1 and 4
Removed the bowl and the jets Main, pilot, air screw and used compressed air to make sure jets are clean and air ways best as possible.
Taken the carb top off and removed the slide and the rubber thing looks fine with no holes.
The header gets warm put not hot like the other 3.
I am out of ideas - new plugs all round, the plug gets a little black if run for to long but a 1min start up - fart, back fire remove plug and only a very light petrol smell.
Checked spark on 4.
Looked at removing carbs but what a nightmare with the airbox in place, I gave up it was so difficult and did the work on the carb best I could in place.
I think its petrol... needs vacuum to lift the slide... bowl is full of fuel.
drain 3 and 4 looks like the same amount.