Top Speed 2001 FZS600??

[unfazed]

Have you checked the air filter, always a good place to start when top speed is down, if it can't breathe it can't go fast.
If it is ok there are two variations of restrictor kit available see pics
I have had 140 on the clock a few years ago two up on the way home from a MotoGp race. :eek
Probably the real top speed of a Red One :lol

Are you sure the noise is from the front, if so check the mudguard is fitted correctly and the tyre is the correct size 110/70 X 17 not a 120/70 X 17 as it will rub the mudguard

Also spin the rear wheel while on the stand as it may be from the front sprocket area.

As for the gear change issue, while it could be a bent or worn selector it could also be a wrong fitted gear lever

Check the punch mark on the gear shaft aligns with the slot in the gear lever

See pic