Dire need of help,bike won't go faster than 60kmh after 2 kms of riding

[Gibon]

Im having same problems. Im hoping my carbs come back fully serviced. I was cleaning the fuel tap and went on youtube to check what to do..... rust in tank ect.
i came across this (hope the link shows) https://youtu.be/jxItIFnjs0M
Im no expert and have only owned this bike a week or so.
Mine is a GS 500 E 1997
GOOD LUCK

as i mentioned this bike has no petcock never had and ran amazing until i opened it:hithead:

[Gibon]

last update,after taking out the carbs and adjusting the floats and cleaning them one last time bike finally seems to be running fine it hiccups from time to time but its still acceptable thank you all for your help