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Hello Everyone, New member from Australia. Been riding Bandits for 6 years and have owned 9 so far and still counting. I do track days and drag racing, done engine swaps, suspension, tear downs and rebuilds. I've got an issue I've tried to tune out / fix for a few months now but I think Ill ask the collective knowledge base before I hurt my back anymore stooping over a bike. The Bike... 2004 GSF1200S 36,000km Slip on exhaust K&N with 1.5" hole mod to airbox lid PAIR system removed and plugged 17.5 pilot jets @ 3 turns out on the screws (have tried 2, 2.5, 3.5 and 4 turns out) 110 main jets standard needles on lower most clip position Standard slide springs but shortened free length by 20mm New NGK JR9B plugs What it does... Quarter mile drags, great immediately off the line, wheelies easily but as soon as you get to approx 40% throttle it dies almost completely. Scary shit when you are in a crouch and then the power stops. Can hear it pop, burble and fart out the exhaust but it will then come back on and will take about 90% throttle and will scream down the rest of the strip. Give it 100% throttle you can feel the power go soft. It does 13.2 second quarters consistently with this condition but way way too dangerous to continue in the hope it will clear itself like it was just some shit in the fuel. Should be able to pull 11.5's so we are way off the mark. Also if you free rev it to around 5,000rpm - 6,500rpm you can hear the exhaust crackle like a misfire. What I have tried... New plugs Different coils Different CDI checked and adjusted TPS and seems to have a uniform linear resistance reading Cleaned out carbs again including all jets and emlusion tubes checked float levels all 13mm Set pilots to exactly 3 turns out before reinstalling checked carb sync was all good Checked battery voltage and charging voltage within spec Fuel tap flows easily when it is supposed to Any suggestions are warmly accepted. Cheers and thanks!