So i have 04 hayabusa and in 1st gear and only in first gear. As i accelerate around 3 thru 6 rpms it jerks bad. When i switch to 2nd it rides smooth same as 3rd thru 5th. It only jerks in first gear. I changed all spark plugs cleaned chains an fresh oil change. There is no F1 code. The bike has no pc or upgrades. All stock. Bike has been sitting for a year tho.