Hmmm, my KTM 125 (street legal) does over 140 kph. Could do more if I geared for it and improved the enduro aerodynamics.
Getting up to 66 kph (9500+ rpm) and great reliability out of my Grubee with only slightly hand modified stock parts and no pipe on a 44t sprocket. I know I could get more with a shifter or taller sprocket.
My spokes and brakes are a serious risk at these speeds. Why would you need more?
Of course I know the need for speed and am still looking for more out of my Grubee, more as an addiction rather than a need. I am not looking for speed as much as power and speed can be a measure of it. I will probably sprocket up and make speed attempts to see what is possible.
Steve